Objective To investigate whether human placenta tissue (PT) CD133SUP>+/SUP> cells possess the high proliferative potential colony forming cells(HPP-CFC) and analyze its properties in order to verify that human PT contains primitive hematopoietic stem/progenitor cells(HSPC). Methods Single cell suspension liquid of human PT was prepared by mechanical method. After that the mononucler cells(MNC) from PT was separated by Histopaque-1007 agent. CD133SUP>+/SUP> cells contained in MNC were isolated and purified by magnetic activated cell sorting(MACS) method. After 28 days of HPP-CFC expansion culture of CD133SUP>+/SUP> cells, the frequency and morphology of HPP-CFC were counted and observed. Phenotypes of purified CD133SUP>+/SUP> cells and HPP-CFC were analyzed by flow cytometer(FCM). In parallel, human umbilical cord blood(UCB) samples underwent the same protocols for comparison. Results After 28 days of culture the expansion fold of PTSUP>-/SUP>CD133SUP>+/SUP> cells was 266, lower than that of UCB-CD133SUP>+/SUP> cells which was 362 (P<0.01). The number of HPP-CFC in CD133SUP>+/SUP> cells derived from human PT and UCB were (32.4±11.2)/5×10SUP>3/SUP> and (17.7±5.7)/5×10SUP>3/SUP> respectively, the number of the former obviously higher than that of the latter (P<0.01). FCM analysis results showed that, except for CD133SUP>+/SUP>CD34SUP>-/SUP> subset from UCB-CD133SUP>+/SUP> cells, the proportion of CD133SUP>+/SUP>CD34+, CD133SUP>-/SUP>CD34SUP>+/SUP> subsets both from PT- and UCB-CD133SUP>+ /SUP>cells and CD133SUP>+/SUP>CD34SUP>- /SUP>subset from PT-CD133SUP>+/SUP> cells were decreased through 4 weeks of culture BR>.Conclusion Human PT-CD133SUP>+ /SUP>cells can form HPP-