Mixed connective tissue disease (MCTD) was first defined in 1972 as a condition characterized by features of systemic lupus erythematosus (SLE), systemic sclerosis (SSc), polymyositis/dermatomyositis, and rheumatoid arthritis (RA) as well as the presence of high-titer anti-U1small nuclear anti-ribonucleoprotein (anti-RNP) antibodies. A 32-year- old female housewife presented with a complaint of itching over whole body in the past 2 months, generalized weakness and Arthralgia (Joint pain) with difficulty in standing from sitting position in the last 1.5 years, generalized edema with a four-months. Particularly, in this case report systemic sclerosis, systemic lupus erythematosus and polymyositis suggests that patient is suffering from mixed connective tissue disorder. The patient was also diagnosed on the basis of clinical pattens. RA33- positive group showed major proportions of SLE- associated antibodies and low level of serum complement components. Generally, patients with MCTD are given NSAIDs to relieve symptoms and immunosuppressants to depress autoimmune reaction.