OBJECTIVE To investigate the clinical characteristics of multiple myeloma complicated with hepatitis B virus(HBV)infection.METHODS A total of 250 patients with multiple myeloma were selected as multiple myeloma group and 250 cases of physical examination were selected as control group in hospital from January Jan.2010 to December Dec.2016.Patients with multiple myeloma were divided into HBsAg positive group(n=22)and HBsAg negative group(n=228)according to whether HBsAg was positive.The serum hepatitis virus...