Background: Psoriasis is a common and genetically determined skin disease, which is frequent throughout the world. Objective: To perform a descriptive clinical study of 200 cases of psoriasis in Ahwaz. Patients and Methods: This study was performed from November 1997 to April 1999 on 200 psoriatic patients attended a private skin clinic in Ahwaz. Data were collected from patients and entered in questionnaires. Results: 56% of the patients were female and 44% were male. The age of onset was in the 1st, 2nd, 3rd and 4th decades in 24.2%, 33.5%, 18.5% and 10%, respectively. Their age was in the 1st, 2nd, 3rd and 4th decades in 23.5%, 28.5%, 17.5% and 14%, respectively. Only few cases referred with later ages of onset. In 40% of the cases the disease started from the scalp. 9% of the patients reported positive Koebner phenomenon. A positive family history for psoriasis was found in 25%. Nail involvement was detected in 39% of the patients. Conclusion: Psoriasis in Ahwaz shows a similar pattern to the other parts of world.