Early diagnosis and treatment of rhabdomyolysis are very important, but difficult to achieve for some atypical cases. Our study was aimed at determining the diagnostic value of ultrasonography in rhabdomyolysis caused by different factors. The study enrolled 50 patients with rhabdomyolysis diagnosed in our hospital. Among the 50 cases (mean age = 38.4 y, 22 women) of rhabdomyolysis, 26 cases (mean age = 35.5 y, 8 women) were induced by exercise. During the patients' first visit, 5 cases (mean age = 30.6 y, 1 woman) were suspected of having rhabdomyolysis and were diagnosed by clinicians; 12 cases (mean age = 34.8 y, 5 women) were correctly diagnosed under ultrasound; and 9 cases (mean age = 39.2 y, 2 women) were misdiagnosed. Ultrasound did not play a critical role in 24 patients (mean age = 41.5 y, 14 women) with rhabdomyolysis caused by trauma, infection, crayfish consumption, drugs, alcohol and heat stroke. We then concluded that exercise-induced rhabdomyolysis is a common type of rhabdomyolysis. Ultrasonography plays an important role in the early diagnosis of exercise-induced rhabdomyolysis but has limited value in the diagnosis of rhabdomyolysis caused by other etiologies.