The present experiment was to study the effect of stromal cell infusion on hematopoietic recovery after peripheral blood stem cell transplantation in mice. BALB/c mice pre conditioned with high dose chemotherapy/radiotherapy were infused with peripheral blood stem cells (PBSCT group) or a combination of peripheral blood stem cells and bone marrow stromal cells (experimental group). Four week survival rate, white blood cell (WBC) count, bone marrow nucleated cells (BMNC), granulocyte macrophage colony forming units (GM CFU), fibroblast colony forming units (F CFU) were determined. The results showed that survival rate, BMNC, GM CFU, and F CFU were significantly higher in experimental group than that in PBSCT group ( P