Objective To analyze the relationship between the cell proliferation and flow fields inside theβ-tricalcium phosphate(β-TCP)scaffold with the computational fluid dynamics. Methods Theβ-TCP scaffolds combined with mesenchymal stem cells were perfused dynamically with a bioreactor for several weeks. The histological and morphometric studies were performed. The CFD modeling was established to reveal the relationship between the cell proliferation and the flow field. Results Histological study showed that the cells proliferated through the whole scaffold along with the time. The cells formed a continuous monolayer in the first week. Some pores were fully filled with cells after 2 weeks' culture. Most of pores were fully filled after 4 weeks' culture, while in some areas the cell coverage decreased. The CFD modeling showed that the optimal fluid velocity and shear stress for the cell proliferation were 0.14~0.64 mm/s and 0.0029~0.017 Pa respectively. Conclusion The microenvironment including the fluid velocity and shear stress had the effect on the cell proliferation inside the scaffold. The size of the interconnecting passages of the pores inside the scaffold changed during the cell proliferation. So did the microenvironment. These factors should be taken into account during the design of scaffold for bone tissue engineering.