Iranian society in the twentieth century is a live image of three identities namely Islamic, Persian and Modern. The purpose of this study is developing and validation of Implicit Association test (IAT) for measurement of Islamic, Iranian and Modern identities. The main question of this research is whether the developed task has a suitable reliability and validity for evaluating Islamic, Iranian and Modern identities? The research design of this study is ex-post facto and statistical population consists of all 19 to 30 year old students in Universities of Tehran. In the first step of this study for validation of IAT, 100 students of Shahid Beheshti University were selected and to the next step 80 students from Tehran Universities completed IAT, Depression, Anxiety and Stress Scale (DASS-21), and Islamic, Iranian and Modern questionnaires.  Results show high validity of IAT and high reliability of participants’ answers to this test.