diff --git a/MJExtension/NSObject+MJKeyValue.m b/MJExtension/NSObject+MJKeyValue.m
index 1515d229..43d93e7d 100755
--- a/MJExtension/NSObject+MJKeyValue.m
+++ b/MJExtension/NSObject+MJKeyValue.m
@@ -16,6 +16,26 @@
 #import "NSString+MJExtension.h"
 #import "NSObject+MJClass.h"
 
+@implementation NSDecimalNumber(MJKeyValue)
+
+- (id)standardValueWithTypeCode:(NSString *)typeCode {
+    // 由于这里涉及到编译器问题, 暂时保留 Long, 实际上在 64 位系统上, 这 2 个精度范围相同,
+    // 32 位略有不同, 其余都可使用 Double 进行强转不丢失精度
+    if ([typeCode isEqualToString:MJPropertyTypeLongLong]) {
+        return @(self.longLongValue);
+    } else if ([typeCode isEqualToString:MJPropertyTypeLongLong.uppercaseString]) {
+        return @(self.unsignedLongLongValue);
+    } else if ([typeCode isEqualToString:MJPropertyTypeLong]) {
+        return @(self.longValue);
+    } else if ([typeCode isEqualToString:MJPropertyTypeLong.uppercaseString]) {
+        return @(self.unsignedLongValue);
+    } else {
+        return @(self.doubleValue);
+    }
+}
+
+@end
+
 @implementation NSObject (MJKeyValue)
 
 #pragma mark - 错误
@@ -138,54 +158,53 @@ - (instancetype)mj_setKeyValues:(id)keyValues context:(NSManagedObjectContext *)
                 } else { // 字典数组-->模型数组
                     value = [objectClass mj_objectArrayWithKeyValuesArray:value context:context];
                 }
-            } else {
-                if (propertyClass == [NSString class]) {
-                    if ([value isKindOfClass:[NSNumber class]]) {
-                        // NSNumber -> NSString
-                        value = [value description];
-                    } else if ([value isKindOfClass:[NSURL class]]) {
-                        // NSURL -> NSString
-                        value = [value absoluteString];
+            } else if (propertyClass == [NSString class]) {
+                if ([value isKindOfClass:[NSNumber class]]) {
+                    // NSNumber -> NSString
+                    value = [value description];
+                } else if ([value isKindOfClass:[NSURL class]]) {
+                    // NSURL -> NSString
+                    value = [value absoluteString];
+                }
+            } else if ([value isKindOfClass:[NSString class]]) {
+                if (propertyClass == [NSURL class]) {
+                    // NSString -> NSURL
+                    // 字符串转码
+                    value = [value mj_url];
+                } else if (type.isNumberType) {
+                    NSString *oldValue = value;
+                    
+                    // NSString -> NSDecimalNumber, 使用 DecimalNumber 来转换数字, 避免丢失精度以及溢出
+                    NSDecimalNumber *decimalValue = [NSDecimalNumber decimalNumberWithString:oldValue locale:nil];
+                    
+                    // 检查特殊情况
+                    if (decimalValue == NSDecimalNumber.notANumber) {
+                        value = @(0);
+                    }else if (propertyClass != [NSDecimalNumber class]) {
+                        value = [decimalValue standardValueWithTypeCode:type.code];
+                    } else {
+                        value = decimalValue;
                     }
-                } else if ([value isKindOfClass:[NSString class]]) {
-                    if (propertyClass == [NSURL class]) {
-                        // NSString -> NSURL
-                        // 字符串转码
-                        value = [value mj_url];
-                    } else if (type.isNumberType) {
-                        NSString *oldValue = value;
-                        
-                        // NSString -> NSNumber
-                        if (type.typeClass == [NSDecimalNumber class]) {
-                            value = [NSDecimalNumber decimalNumberWithString:oldValue];
-                        } else {
-                            NSDecimalNumber *decimalValue = [NSDecimalNumber decimalNumberWithString:oldValue];
-                            value = decimalValue == [NSDecimalNumber notANumber] ? @(0) : @(decimalValue.doubleValue);
-                        }
-                        
-                        // 如果是BOOL
-                        if (type.isBoolType) {
-                            // 字符串转BOOL（字符串没有charValue方法）
-                            // 系统会调用字符串的charValue转为BOOL类型
-                            NSString *lower = [oldValue lowercaseString];
-                            if ([lower isEqualToString:@"yes"] || [lower isEqualToString:@"true"]) {
-                                value = @YES;
-                            } else if ([lower isEqualToString:@"no"] || [lower isEqualToString:@"false"]) {
-                                value = @NO;
-                            }
+                    
+                    // 如果是BOOL
+                    if (type.isBoolType) {
+                        // 字符串转BOOL（字符串没有charValue方法）
+                        // 系统会调用字符串的charValue转为BOOL类型
+                        NSString *lower = [oldValue lowercaseString];
+                        if ([lower isEqualToString:@"yes"] || [lower isEqualToString:@"true"]) {
+                            value = @YES;
+                        } else if ([lower isEqualToString:@"no"] || [lower isEqualToString:@"false"]) {
+                            value = @NO;
                         }
                     }
-                } else if ([value isKindOfClass:[NSNumber class]] && propertyClass == [NSDecimalNumber class]){
-                    // 过滤 NSDecimalNumber类型
-                    if (![value isKindOfClass:[NSDecimalNumber class]]) {
-                        value = [NSDecimalNumber decimalNumberWithDecimal:[((NSNumber *)value) decimalValue]];
-                    }
                 }
-                
-                // value和property类型不匹配
-                if (propertyClass && ![value isKindOfClass:propertyClass]) {
-                    value = nil;
+            } else if ([value isKindOfClass:[NSNumber class]] && propertyClass == [NSDecimalNumber class]){
+                // 过滤 NSDecimalNumber类型
+                if (![value isKindOfClass:[NSDecimalNumber class]]) {
+                    value = [NSDecimalNumber decimalNumberWithDecimal:[((NSNumber *)value) decimalValue]];
                 }
+            } else if (propertyClass && ![value isKindOfClass:propertyClass]) { // value和property类型不匹配
+                value = nil;
             }
             
             // 3.赋值
diff --git a/MJExtensionDemo/Base.lproj/Main.storyboard b/MJExtensionDemo/Base.lproj/Main.storyboard
index 942f0bc4..75f3f5cf 100644
--- a/MJExtensionDemo/Base.lproj/Main.storyboard
+++ b/MJExtensionDemo/Base.lproj/Main.storyboard
@@ -1,7 +1,9 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="13122.16" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="BYZ-38-t0r">
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="14868" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="BYZ-38-t0r">
+    <device id="retina6_1" orientation="portrait" appearance="light"/>
     <dependencies>
-        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="13104.12"/>
+        <deployment identifier="iOS"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="14824"/>
         <capability name="Safe area layout guides" minToolsVersion="9.0"/>
         <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
     </dependencies>
@@ -9,16 +11,26 @@
         <!--View Controller-->
         <scene sceneID="tne-QT-ifu">
             <objects>
-                <viewController id="BYZ-38-t0r" customClass="ViewController" customModuleProvider="" sceneMemberID="viewController">
+                <viewController id="BYZ-38-t0r" customClass="ViewController" sceneMemberID="viewController">
                     <view key="view" contentMode="scaleToFill" id="8bC-Xf-vdC">
-                        <rect key="frame" x="0.0" y="0.0" width="375" height="667"/>
+                        <rect key="frame" x="0.0" y="0.0" width="414" height="896"/>
                         <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
+                        <subviews>
+                            <label opaque="NO" userInteractionEnabled="NO" contentMode="left" horizontalHuggingPriority="251" verticalHuggingPriority="251" fixedFrame="YES" text="Find examples in UnitTest files." textAlignment="center" lineBreakMode="tailTruncation" baselineAdjustment="alignBaselines" adjustsFontSizeToFit="NO" translatesAutoresizingMaskIntoConstraints="NO" id="Trl-sJ-gBw">
+                                <rect key="frame" x="36" y="368" width="341" height="160"/>
+                                <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
+                                <fontDescription key="fontDescription" type="system" pointSize="20"/>
+                                <nil key="textColor"/>
+                                <nil key="highlightedColor"/>
+                            </label>
+                        </subviews>
                         <color key="backgroundColor" red="1" green="1" blue="1" alpha="1" colorSpace="custom" customColorSpace="sRGB"/>
                         <viewLayoutGuide key="safeArea" id="6Tk-OE-BBY"/>
                     </view>
                 </viewController>
                 <placeholder placeholderIdentifier="IBFirstResponder" id="dkx-z0-nzr" sceneMemberID="firstResponder"/>
             </objects>
+            <point key="canvasLocation" x="137.68115942028987" y="137.94642857142856"/>
         </scene>
     </scenes>
 </document>
diff --git a/MJExtensionTests/MJExtensionTests.m b/MJExtensionTests/MJExtensionTests.m
index 8d823640..44b8f64c 100644
--- a/MJExtensionTests/MJExtensionTests.m
+++ b/MJExtensionTests/MJExtensionTests.m
@@ -30,16 +30,19 @@ - (void)testJSON2Model {
     NSDictionary *dict = @{
                            @"name" : @"Jack",
                            @"icon" : @"lufy.png",
-                           @"age" : @"20",
+                           @"age" : @"2147483647",
+                           @"age2": @"4294967295",
                            @"height" : @1.55,
-                           @"money" : @"100.9",
+                           @"money" : @"100.7777777",
                            @"sex" : @(SexFemale),
                            @"gay" : @"1",
                            @"speed" : @"120.5",
-                           @"identifier" : @"3443623624362",
+                           @"identifier" : @"9223372036854775807",
+                           @"identifier2" : @"18446744073709551615",
                            @"price" : @"20.3",
                            @"rich" : @"2",
-                           @"collect" : @"40个"
+                           @"collect" : @"40个",
+                           @"alien": @"yr Joking"
                            };
     
     // 2.将字典转为MJUser模型
@@ -48,16 +51,19 @@ - (void)testJSON2Model {
     // 3.检测
     XCTAssert([user.name isEqual:@"Jack"]);
     XCTAssert([user.icon isEqual:@"lufy.png"]);
-    XCTAssert(user.age == 20);
-    XCTAssert(user.height.doubleValue == 1.55);
-    XCTAssert(user.money.doubleValue == 100.9);
+    XCTAssert(user.age == INT_MAX);
+    XCTAssert(user.age2 == UINT_MAX);
+    XCTAssert([user.height isEqualToNumber:@(1.55)]);
+    XCTAssert([user.money compare:[NSDecimalNumber decimalNumberWithString:@"100.7777777"]] == NSOrderedSame);
     XCTAssert(user.sex == SexFemale);
-    XCTAssert(user.gay == YES);
+    XCTAssert(user.gay);
     XCTAssert(user.speed == 120);
-    XCTAssert(user.identifier == 3443623624362);
+    XCTAssert(user.identifier == LONG_LONG_MAX);
+    XCTAssert(user.identifier2 == ULONG_LONG_MAX);
     XCTAssert(user.price == 20.3);
-    XCTAssert(user.rich == YES);
+    XCTAssert(user.rich);
     XCTAssert(user.collect == 40);
+    XCTAssert(!user.alien);
 }
 
 - (void)testJSON2NumberModel {
diff --git a/MJExtensionTests/Model/MJUser.h b/MJExtensionTests/Model/MJUser.h
index dee6bfe0..82127073 100644
--- a/MJExtensionTests/Model/MJUser.h
+++ b/MJExtensionTests/Model/MJUser.h
@@ -19,7 +19,8 @@ typedef enum {
 /** 头像 */
 @property (copy, nonatomic) NSString *icon;
 /** 年龄 */
-@property (assign, nonatomic) unsigned int age;
+@property (assign, nonatomic) int age;
+@property (assign, nonatomic) unsigned int age2;
 /** 身高 */
 @property (strong, nonatomic) NSNumber *height;
 /** 财富 */
@@ -32,6 +33,7 @@ typedef enum {
 @property (assign, nonatomic) NSInteger speed;
 /** 标识 */
 @property (assign, nonatomic) long long identifier;
+@property (assign, nonatomic) unsigned long long identifier2;
 /** 价格 */
 @property (assign, nonatomic) double price;
 /** 赞 */
@@ -41,4 +43,7 @@ typedef enum {
 /** 富有 */
 @property (assign, nonatomic) BOOL rich;
 
+/** 一定为 NO, 用来测试无效数据 @"alien": @"yr Joking"  */
+@property (assign, nonatomic) BOOL alien;
+
 @end