To explore clinical and pathological characteristics of idiopathic inflammatory myopathy with anti-HMGCR or anti-SRP antibodies. Methods: Total 5 patients positive for anti-HMGCR/anti-SRP antibody with idiopathic inflammatory myopathy were enrolled in this study. Risk factors, clinical manifestations, laboratory findings, electromyography, muscle MRI, muscle pathology, myositis autoantibody, and drug treatment information were collected and analyzed. Results: Idiopathic inflammatory myopathy patients that were anti-HMGCR/anti-SRP antibody-positive displayed a large variation in clinical symptoms with most patients showing muscle weakness. Serum creatine kinase level was elevated in all patients. Electromyographical studies showed typical myogenic impairments in all patients. Muscle MRI was mainly characterized by muscle edema. Pathological manifestations of muscle biopsy showed necrotizing myopathy in 3 patients that were anti-HMGCR/anti-SRP antibody-positive, occasionally seen muscle fiber necrosis in 1 patient, and polymyositis in 1 patient. Of the 2 patients that were anti-HMGCR antibody-positive, 1 was taking statin, and the other was taking antipsychotics. Of the 3 patients that were anti-SRP antibody-positive, 1 patient had autoimmune disease, 1 patient had been taking statin long-term, and the other patient had no clear cause of disease. Results of hormone therapy varied; 2 patients received gamma globulin therapy, and 1 patient received immunization inhibitor treatment. Conclusion: The clinical manifestations of idiopathic inflammatory myopathy with anti-HMGCR/anti-SRP antibody are different. EMG can only be used to assess muscle damage, and muscle biopsy and myositis autoantibodies antibody are more helpful for diagnosis and determination of myopathy type. The curative effect varies from type to type.