Returning bool value from ajax is not similar to any simple function that returns the bool value. BUT DON'T WORRY! it isn't even too difficult. it's just slightly different. Solution var alreadyExists = function () { var role = $("#UserRole").val(); var notexists = false; $.ajax ({ url: "@(Url.Action("checkExists", "UserManagement"))", data: { role: role }, contentType:... Continue Reading →