An increased enthusiasm on teacher accountability, in recent times, has led policy makers and teachers to a significant care over evaluating teachers' success. To this aim, a 40-item Teacher Success questionnaire was developed and validated by the application of the Rasch model. The Rasch model is used to decide whether the scores of an instrument are meaningful, significant, and purposive. The test was developed in Persian to be used for Iranian teachers. The Rasch rating scale model for polytomous data was used to examine the psychometric qualities of the scale in terms of dimensionality, use of response category, sample appropriateness, and reliability. The test was administrated to 828 Iranian EFL students. The results revealed that the Rasch model fits the test after deleting 8 items from the scale. Moreover, it is confirmed that the scale enjoyed suitable reliability. This proposes that the questionnaire is potentially valid and can be used as a measure of teachers' success in the Persian language settings.