Asthma is one of the most common chronic diseases worldwide and factors such as genetic, environmental and psychological factors play an important role in the maintenance of emotional and mood problems Caused by the disease. There are many variables which relate to this issue and influence on it. Therefore, this study aimed at investigating the relationship between neuroticism, illness perception, social support and Cognitive Emotion Regulation with depression among patient of asthma to answer this question, are these psychological variables able to predict meaningfully the depression of these patients. The research method is descriptive in multi-variable correlational design (step by step regression)., to do so 120 patient with asthma were selected using at-hand sampling and were studied; they completed the perception social support questionnaires (1988), Beck depression inventory (1996), Cognitive Emotion Regulation inventory (2001), Illness perception (2006), Big five personality trait scale (1986). Depression had a significant and positive relationship with illness perception (P<0/001), negative cognitive emotion Regulation (P<0/001) and neuroticism (P<0/001). Positive emotional regulation had a negative relationship with depression (P<0/05). Based on the results illness perception, could predict 37 percent of depression in patient with asthma. So it seems that a high level of awareness and understanding of the disease have been effective in increasing symptoms of depression.