passing value between 2 Windows Form?

Exactly the same way. Form2 from2 = new Form2(); form2.ShowDialog(); string test = form2.MyValue; // and so on... You could also get the dialogs result with DialogResult dr = form2.ShowDialog(). (You have to assign dialog results to buttons in your Form2). Simon

Thanks for your help. But in my case, when the Form2 be declared " Form2 form2 = new Form2(); " it need to call the "form2.ShowDialog();" method then make some processes. How can I return the value back to the Form1?

Hi Create access methods or properties. Example: Form1 should have access to a value of Form2: public class Form1 { // ... constructor and designer code removed for clarity. private Form2 form2 = new Form2(); // A method, maybe an button click event handler method. private void Test() { // Access myValue of Form2 instance. string test = form2.GetMyValue(); // or... string test1 = form2.MyValue; } } public class Form2 { // ... constructor and designer code removed for clarity. private string myValue = "Hi there..."; // Access method. public string GetMyValue() { return myValue; } // Access property public MyValue { get { return myValue; } set { myValue = value; } } Simon }