diff --git a/codec.go b/codec.go
index 321014e..206e823 100644
--- a/codec.go
+++ b/codec.go
@@ -1,6 +1,7 @@
 package udecimal
 
 import (
+	"bytes"
 	"database/sql"
 	"database/sql/driver"
 	"encoding"
@@ -236,6 +237,9 @@ func (d Decimal) MarshalJSON() ([]byte, error) {
 	return []byte(`"` + d.stringBigInt(true) + `"`), nil
 }
 
+// nullValue represents the JSON null value.
+var nullValue = []byte("null")
+
 // UnmarshalJSON implements the [json.Unmarshaler] interface.
 func (d *Decimal) UnmarshalJSON(data []byte) error {
 	// Remove quotes if they exist.
@@ -243,6 +247,11 @@ func (d *Decimal) UnmarshalJSON(data []byte) error {
 		data = data[1 : len(data)-1]
 	}
 
+	// null value.
+	if bytes.Equal(data, nullValue) {
+		return nil
+	}
+
 	return d.UnmarshalText(data)
 }
 
diff --git a/codec_test.go b/codec_test.go
index 6074400..dbe75ca 100644
--- a/codec_test.go
+++ b/codec_test.go
@@ -180,6 +180,13 @@ func TestUnmarshalJSON(t *testing.T) {
 	}
 }
 
+func TestUnmarshalJSONNull(t *testing.T) {
+	var test Test
+	err := json.Unmarshal([]byte(`{"price": null}`), &test)
+	require.NoError(t, err)
+	require.True(t, test.Test.IsZero())
+}
+
 func TestMarshalBinary(t *testing.T) {
 	testcases := []struct {
 		in string