It is still under debate whether bone marrow (BM) or peripheral blood (PB) should be the preferred stem cell source in adult patients undergoing allogeneic stem cell transplantation for hematological malignancies. After systematic literature search we identified nine randomised controlled trials comparing BM and PB as stem cell source from 2341 total hits. Meta-analysis involving 1521 patients showed a statistically significant reduction in overall and extensive chronic GvHD for patients transplanted with BM (HR 0.72; 95% CI 0.61 to 0.85 and HR 0.69; 95% CI 0.54 to 0.9), but no difference in overall and disease-free survival. In the related donor setting, data from 2/8 studies demonstrated a significant increase of relapse incidence for BM (HR 2.73; 95% CI 1.47 to 5.08). This systematic review demonstrates that the current clinical standard to use peripheral blood stem cells instead of bone marrow for allo-SCT is not inferior with regard to the primary outcome overall survival.