We retrospectively compared the outcomes of 225 patients with adult acquired aplastic anemia (AA) who underwent allogeneic hematopoietic stem cell transplantation (alloHSCT) from matched related donors (MRDs), and those treated by alloHSCT from alternative donors (ADs). Univariate and multivariate analyses of factors associated with survival were performed. Multivariate analysis showed that age at alloHSCT of ≤31 years, MRD, successful engraftment, absence of acute graft-versus-host disease (aGVHD), and platelet engraftment at ≤21 days, were independent predictors of longer survival. In addition, time to aGVHD and cumulative nonrelapse mortality (NRM) were better in MRD than in AD recipients. Using propensity score matching (PSM), we performed a case-control study comparing 25 patients in each group who underwent alloHSCT from MRDs and ADs. Pretransplantation clinical factors were well balanced in either group. Median survival time was similar, and no statistically significant difference in transplantation outcomes was apparent when MRD and AD recipients were compared. In conclusion, our results suggest that alloHSCT from an AD should be considered earlier in adult patients with AA who do not have an MRD.