This study was an attempt to investigate the impact of personality types on language learning by a group of Iranian teachers. Therefore, 30 male and female teachers as English learners teaching in different fields in Quchan a city in north east in Iran were selected as research participants through convenience sampling. The instruments used to gather the data were the Myers and Briggs Test Inventory (MBTI) for identifying their personality types, and another inventory was the teacher's final scores of their course as a proficiency test for identifying their level of success in language learning. To analyze the data, SPSS software was used. The results of the study showed that there was a significant and meaningful relationship between some personality types and foreign language learning by Iranian teachers. Also some results show that sometimes personality doesn't affect learning English so there must be other reasons that affect teacher's learning language.