Clearance of hepatitis B surface antigen (HBsAg) is an ideal therapeutic goal for patients with chronic hepatitis B virus (HBV) infection. Haematopoietic stem cell transplantation (HSCT) is the most effective therapy for a variety of haematological diseases. For patients with chronic HBV infection who received allo-HSCT, recipient hepatitis B serological status might change after allo-HSCT; however, data on the loss of HBsAg following allo-HSCT are relatively rare. We first reviewed patients with chronic HBV infection who received allo-HSCT in our centre from 2010 to 2020, and 125 patients were included in our study. A total of 62 patients (49.6%) with chronic HBV infection achieved HBsAg loss after allo-HSCT. Positivity for HBeAb and HBsAb in donors as well as no cytomegalovirus (CMV) infection were identified as independent risk factors for HBsAg loss after allo-HSCT. A predictive model including positivity for HBeAb and HBsAb in donors and no CMV infection was subsequently developed and performed well with effective discrimination and calibration. In addition, patients could benefit when this model is used in the clinic, as revealed via decision-curve analysis (DCA). However, multicentre prospective studies are required for validation.