Abstract: Aim: The aim of this study was to determine the clinical and the laboratory features of scleroderma in Iranian patients. Methods: This is a prospective study done on 350 patients from 1975 to 1995. The diagnosis of scleroderma was based on the clinical and the skin biopsy. One hundred clinical and laboratory data were completed for every patients . Results: The mean age was 29.7 years with a standard deviation (SD) of 13.1, standard error of mean (SEM) of 0.7. 85% of patients were Females. The females to male ratio was 6/1. Manifestations at the disease onset were as follow: Raynaud's phenomenon was seen in 55% of the patient, limb and face skin sclerosis in 28%, edematous skin in 6%, and articular manifestations in 17%. Clinical Manifestations: Fever was seen in 6% of the patients, loss of appetite in 10%, and weight loss in 25%. The skin sclerosis was seen in limbs in 47%, face in 87% and trunck in 20%. Telangiectasia was seen in 30%, joint deformities due to skin thickening in 5%, dysphagia in 42%, esophagitis in I4.2%, esophageal dysmotility in 28%, dvspnea in 36.5%, dry cough in 8%, productive cough in 7%, heart failure in 3%, malignant hypertension in 4%, renal failure in 3%, Raynaud's phenomenon in 80%, pitting ulcer in 50%, finger gangrene in 12% and osteolysis in 25% of patients. Lab. data were: Anemia was seen in 10% of patients, urine sediment abnormality in 18%, elevated sedimentation rate in 30%, anti-nuclear antibody ( FANA ) in 50%, and Rheumatoid Factor in 24% of patients. Conclusion: 1- Raynaud's phenomenon and FANA was seen less often than in Western studies. 2- Malignant hypertension as a manifestation of renal involvement and Cardiac Involvement were uncommon Iranian patients.