Background: Obesity is becoming an important issue for health promotion. The World Health Organization estimated that around 1.5 billion adults were overweight (body mass index (BMI) 25 kg/m2) and about 500 million people were obese (BMI 30 kg/m2) in 2008. The relationship between obesity and mental health is also considered important. In a community-based study, obesity was positively associated with several mental disorders, especially mood disorders and anxiety disorders. The aim of the study is the assessment of current and lifetime psychiatric disorders among morbidly obese patients. Methods: This case control study was conducted on 60 participants from outpatient clinic of GIT surgery unit and community. All participants were subjected to: Body weight and body mass index, Psychiatric interview for diagnosis of psychiatric disorders by Arabic version of MINI, Scale for diagnosis of Bulimia nervosa by Shokeer, Scale for diagnosis of Anorexia Nervosa by Shokeer, Binge Eating Disorder Screener-7, Eating attitude test, Hamilton Depressions Rating Scale and Hamilton anxiety scale. Results: There was a significant increase in anxiety in patients with morbid obesity compared to control group. There was a significant difference between both groups showing the high prevalence of depression in patients with morbid obesity. Based on EAT test, there was a significant prevalence of abnormal eating behaviors in patients group compared to none of control group. A screening test for the presence of Binge eating symptoms revealed significant increase of symptoms in patients’ group. Conclusions: Psychiatric disorders are prevalent in morbidly obese patients and are associated with significantly worse quality of life. In addition, morbidly obese patients had significantly worse physical and mental health relative to control group from general population. High rates of psychiatric disorders among morbidly obese patients seem to be the rule rather than an exception.