Previous studies show that psychiatric conditions can influence educational achievements of learners. This study aims to investigate the differences between TEFL students with mental health disorders and normal students in cognitive strategy use in L2 writing. Seventy and two EFL postgraduate and under graduate students of Najafabad Branch, Islamic Azad University participated in this study. They were selected through random sampling. The materials were Quick Oxford Placement Test (QOPT), Beck Depression Inventory (BDI), Modsley Obsessive Compulsive Inventory(MOCI), writing strategy questionnaire, Semi- structured interview. Although, people with OCD and people with depression show cognitive impairment, the study indicates no difference between students with mental health disorders and normal students in cognitive strategy use. It seems that cognitive impairment in OCD and depression does not play an important role in selecting cognitive strategies in writing. Besides the findings of this study, further research is required to show the importance of psychological problems in the process of learning to language teachers in order to help learners in this respect. DOI: 10.5901/mjss.2014.v5n23p882