HLA-haploidentical hematopoietic SCT (HSCT) provides an opportunity for almost all patients who lack HLA-matched sibling donors. The donor availability can be increased by including the collateral related donors (CRDs). We compared clinical outcomes of patients with hematological malignancies, who underwent haploidentical HSCT from CRD (n=30) and immediate related donors (IRDs; n=120). In CRDs, 29 (96.7%) patients achieved sustained engraftment. In CRDs and IRDs, the median times of myeloid recovery were 13 (range 10-20 days) and 14 days (range 12-23 days), and the median times of platelet recovery were 18 (range 7-270) and 15 days (range 7-132 days; P=0.027). The incidences of II-IV acute GVHD were 27.6% versus 39.4% (P=0.058). The 2-year cumulative incidences of chronic GVHD (cGVHD) were 63.3% versus 57.8% (P=0.365). The 2-year incidence of extensive cGVHD of CRDs was significantly higher than that of IRDs (36.7% versus 20.2%, P=0.03). The 2-year incidences of relapse, 3-year probability of OS and leukemia-free survival for the two groups were 26.7% versus 14.8% (P=0.17), 56.7% versus 70.4% (P=0.224) and 50.0% versus 65.4% (P=0.103), respectively. This study shows that haploidentical HSCT from CRDs can provide a safe and effective treatment for patients with hematological malignancies. CRDs could be an alternative when there was no suitable IRDs.