Objective To investigate the effect of density separation of hematopoietic stem/progenitor cells(HSCs) for cord blob banking with storage volume reduction. Methods The separation efficiency of HSCs from cord blood were evaluated using five different densities Ficolls (1. 084, 1 .077,1. 072, 1 .064, 1. 054 g/L). The recovery of nucleated cells(NCs) and HSCs from 41 cord bloods were analyzed by flow Cytometry and blood autoanalyser. Results The recovery of NCs in 1 .064 g/L Ficoll spearated samples was 3. 6% with 86.6% lymphocyte depletion,The purity of CD34 +,the highest one reached 46.6%,was 10.3% on average in mononu clear cells(MNCs),The 1 .064 g/L Ficoll separated cells was easy to form colonies of CFU-GM and BFU-E in vitro. Conclusion The separation of hematopoietic stem/progenitor cells from cord blood was affected by different density Ficoll. The 1 .064 g/L Ficoll separation method was a convennient, practical, efficient method. The separated cells contained a higher percentage of HSCs in MNCs, which was demonstrated to have positive proliferation activity in vitro.