diff --git a/README.md b/README.md
index 822c4fa1..60c5f033 100644
--- a/README.md
+++ b/README.md
@@ -136,6 +136,7 @@ func (f *Float) Get() float64 {}
 
 ```go
 func NewMany2One(id int64, name string) *Many2One {}
+func NewUnassignedMany2One() *Many2One {}
 func (m *Many2One) Get() int64 {}
 
 func NewRelation() *Relation {}
diff --git a/conversion.go b/conversion.go
index a55d4b62..7addc458 100644
--- a/conversion.go
+++ b/conversion.go
@@ -47,7 +47,11 @@ func convertFromStaticToDynamicValue(staticValue interface{}) interface{} {
 	case *Float:
 		v = sv.v
 	case *Many2One:
-		v = sv.ID
+		if sv.ID == 0 {
+			v = false
+		} else {
+			v = sv.ID
+		}
 	case *Relation:
 		v = sv.v
 	default:
diff --git a/types.go b/types.go
index b9886908..53f8deae 100644
--- a/types.go
+++ b/types.go
@@ -124,6 +124,11 @@ func NewMany2One(id int64, name string) *Many2One {
 	return &Many2One{ID: id, Name: name}
 }
 
+// NewUnassignedMany2One create *Many2One value that once set will unassign the current value.
+func NewUnassignedMany2One() *Many2One {
+	return &Many2One{}
+}
+
 // Get *Many2One value.
 func (m *Many2One) Get() int64 {
 	return m.ID