diff --git a/docs/api-references/docs.md b/docs/api-references/docs.md
index 9f06f5dc03b..ed6bd8f0469 100644
--- a/docs/api-references/docs.md
+++ b/docs/api-references/docs.md
@@ -25497,6 +25497,11 @@ github.com/pingcap/tidb-operator/pkg/apis/label.Label
 </em>
 </td>
 <td>
+<p>MatchLabels is used to overwrite generated corev1.TopologySpreadConstraints.NodeSelector.</p>
+<p>corev1.TopologySpreadConstraint generated in component_spec.go will set a
+NodeSelector automatically with some KV.
+Historically, it is l[&ldquo;comp&rdquo;] = &ldquo;&rdquo; for component tiproxy. And we will use
+MatchLabels to keep l[&ldquo;comp&rdquo;] = &ldquo;&rdquo; for old clusters with tiproxy/</p>
 </td>
 </tr>
 </tbody>
diff --git a/pkg/apis/pingcap/v1alpha1/types.go b/pkg/apis/pingcap/v1alpha1/types.go
index 217332f2c27..0f656575091 100644
--- a/pkg/apis/pingcap/v1alpha1/types.go
+++ b/pkg/apis/pingcap/v1alpha1/types.go
@@ -3002,7 +3002,13 @@ type TopologySpreadConstraint struct {
 	// WhenUnsatisfiable is default set to DoNotSchedule
 	// LabelSelector is generated by component type
 	// See pkg/apis/pingcap/v1alpha1/tidbcluster_component.go#TopologySpreadConstraints()
-	TopologyKey string      `json:"topologyKey"`
+	TopologyKey string `json:"topologyKey"`
+	// MatchLabels is used to overwrite generated corev1.TopologySpreadConstraints.NodeSelector.
+	//
+	// corev1.TopologySpreadConstraint generated in component_spec.go will set a
+	// NodeSelector automatically with some KV.
+	// Historically, it is l["comp"] = "" for component tiproxy. And we will use
+	// MatchLabels to keep l["comp"] = "" for old clusters with tiproxy/
 	MatchLabels label.Label `json:"matchLabels"`
 }