Objective To investigate the diagnosis,differential diagnosis,treatment and prognosis of solitary plasmacytoma (SP) and summarize its clinical features for pathological and clinical application.Methods Reviewed the data of 18 patients diagnosed with SP from January 2005 to August 2013.The clinical features,diagnosis,treatment and prognosis were analyzed retrospectively.Results All 18 cases were pathologically confirmed with SP and met the diagnostic criteria of SP.In 18 patients,12 patients were male and 6 patients were female.Four cases of lesion were located at lumbar,each 2 cases of lesion were located at mandible and ribs,each 1 case of lesion was located at sacrum and occipital bone,3 cases of lesion were located at nasal cavity and maxillary sinus,2 cases of lesion was located at pars nasalis pharyngis,each 1 case of lesion was located at parotid,parasternal and peritoneal cavity.All patients were followed up for 54 months,2 patients were died,3 patients were local recurrence,2 patients were transformed to multiple myeloma,others were survival with no tumor.Conclusions As early as possible to diagnose is the key to treat SP.The final diagnosis of SP is based on the histopathological findings and the optimal treatment for patients with SP is surgery combined with moderate dose radiotherapy.