diff --git a/CHANGELOG.md b/CHANGELOG.md
index 899d4b1..fd0cd2c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,11 @@
 Changelog
 =========
 
+v0.3.4 (2023-09-28)
+-------------------
+* Add `Serializable` class
+* Make `BBox` child class of `Serializable`
+
 v0.3.3 (2023-09-28)
 -------------------
 * Update `BBox` class
diff --git a/VERSION b/VERSION
index 87a0871..448a0fa 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-0.3.3
\ No newline at end of file
+0.3.4
\ No newline at end of file
diff --git a/dedocutils/data_structures/bbox.py b/dedocutils/data_structures/bbox.py
index bf69090..310de53 100644
--- a/dedocutils/data_structures/bbox.py
+++ b/dedocutils/data_structures/bbox.py
@@ -5,9 +5,11 @@
 
 import numpy as np
 
+from dedocutils.data_structures.serializable import Serializable
+
 
 @dataclass
-class BBox:
+class BBox(Serializable):
     """
     Bounding box around some page object, the coordinate system starts from top left corner.
     """
diff --git a/dedocutils/data_structures/serializable.py b/dedocutils/data_structures/serializable.py
new file mode 100644
index 0000000..9de5d23
--- /dev/null
+++ b/dedocutils/data_structures/serializable.py
@@ -0,0 +1,16 @@
+from abc import ABC, abstractmethod
+
+
+class Serializable(ABC):
+    """
+    Base class for the serializable objects which we need convert to dict.
+    """
+    @abstractmethod
+    def to_dict(self) -> dict:
+        """
+        Convert class data into dictionary representation.
+        Dictionary key should be string and dictionary value should be json serializable.
+
+        :return: dict with all class data.
+        """
+        pass