diff --git a/pkg/vm/vm.go b/pkg/vm/vm.go
index 27614ea9f..c914fd829 100644
--- a/pkg/vm/vm.go
+++ b/pkg/vm/vm.go
@@ -871,6 +871,9 @@ func (v *VM) execute(ctx *Context, op Instruction, parameter []byte) {
 			}
 			arr[index] = item
 		case *MapItem:
+			if !t.Has(key.value) && len(t.value) >= MaxArraySize {
+				panic("too big map")
+			}
 			t.Add(key.value, item)
 
 		default:
diff --git a/pkg/vm/vm_test.go b/pkg/vm/vm_test.go
index 8cfc83505..d2f09923e 100644
--- a/pkg/vm/vm_test.go
+++ b/pkg/vm/vm_test.go
@@ -734,6 +734,38 @@ func TestSETITEMMap(t *testing.T) {
 	assert.Equal(t, makeStackItem([]byte{0, 1}), vm.estack.Pop().value)
 }
 
+func TestSETITEMBigMapBad(t *testing.T) {
+	prog := makeProgram(SETITEM)
+	vm := load(prog)
+
+	m := NewMapItem()
+	for i := 0; i < MaxArraySize; i++ {
+		m.Add(makeStackItem(i), makeStackItem(i))
+	}
+	vm.estack.Push(&Element{value: m})
+	vm.estack.PushVal(MaxArraySize)
+	vm.estack.PushVal(0)
+
+	vm.Run()
+	assert.Equal(t, true, vm.HasFailed())
+}
+
+func TestSETITEMBigMapGood(t *testing.T) {
+	prog := makeProgram(SETITEM)
+	vm := load(prog)
+
+	m := NewMapItem()
+	for i := 0; i < MaxArraySize; i++ {
+		m.Add(makeStackItem(i), makeStackItem(i))
+	}
+	vm.estack.Push(&Element{value: m})
+	vm.estack.PushVal(0)
+	vm.estack.PushVal(0)
+
+	vm.Run()
+	assert.Equal(t, false, vm.HasFailed())
+}
+
 func TestSIZENoArgument(t *testing.T) {
 	prog := makeProgram(SIZE)
 	vm := load(prog)