We report a case of mixed connective tissue disease in a 35-year-old woman showing typicallaboratory and clinical features. Clinically she suffered from hand edema, arthritis, proximalmuscle weakness, loss of hair and Raynaud's phenomenon. FANA revealed a speckled epidermal nuclear staining pattern. Analysis of serum showed anti RNP antibody positive and antiSm antibody negative. Anti DHA antibody occurred in low titer. The patient showed a promptreponse to prednisone 0.5mg per body weight without any recurrence.