SummaryTo compare the clinical efficacy of porcine anti‐lymphocyte globulin (p‐ALG) and rabbit anti‐thymocyte globulin (r‐ATG) in the treatment of haematological malignancies using haploidentical haematopoietic stem cell transplantation (haplo‐HSCT), this study was conducted. The incidences of neutrophil and platelet engraftment, respectively, were 100%, 93.6% and 94.4%; 100%, 93.6% and 90.3% in p‐ALG 75 mg/kg (n = 57), p‐ALG 90 mg/kg (n = 49), and r‐ATG 7.5 mg/kg (n = 72). The median time to neutrophil engraftment and platelet engraftment were 11, 12 and 12 days (p = 0.032); 13, 14 and 13 days (p = 0.013), respectively. The incidence of grades II–IV acute graft‐versus‐host disease and cumulative incidence of chronic graft‐versus‐host disease were 16.7% versus 12.5% versus 13.3% (p = 0.817) and 14.7% versus 12.1% versus 19.5% in p‐ALG 75 mg/kg, p‐ALG 90 mg/kg and r‐ATG groups. Notably, the cytomegalovirus infection rate in the p‐ALG 75 mg/kg group was significantly lower than the other two groups. The cumulative incidence of 2‐year relapse and 2‐year overall survival rates were similar (p = 0.901, p = 0.497). The lower dose of p‐ALG (75 mg/kg) had a similar efficacy and safety profile compared with r‐ATG (7.5 mg/kg) in the setting of haplo‐HSCT. Therefore, p‐ALG (75 mg/kg) may be an appropriate alternative to r‐ATG in the conditioning regimen of haplo‐HSCT.