Juvenile dermatomyositis ranks fourth among rheumatologic diseases. Two thirds of patients were reported between ages of 4 and 11.5 years girls are usually affected more than boys. The etiology still poorly elucidated. It is a multisystem disease of uncertain etiology that results in nonsuppurative inflammation of striated muscle & skin. The most typical features (heliotrope eyelid rash and Gottron's papules) are pathognomonic. JDM is diagnosed by MRI using T2 weighted images, muscle biopsy and electromyogram.The mainstay of medical therapy is based on immune suppression.