In this study, the effects of wollastonite on proliferation and differentiation of human bone marrow-derived stromal cells (hBMSCs) have been investigated based on a polyhydroxybutyrate-co-hydroxyvalerate (PHBV)/ wollastonite (W) composite scaffolds system. Cell morphology, proliferation, and differentiation were measured. The results showed that the incorporation of wollastonite benefited hBMSCs adhesion, proliferation, and differentiation rate. In addition, an increase of proliferation and differentiation rate was observed when the wollastonite content in the PHBV/W composite scaffolds increased from 10 to 20 wt%. Based on our previous studies on PHBV/W composite discs, the differentiation measurements in this paper further proved that the wollastonite itself can stimulate the hBMSCs to differentiate toward osteoblasts without any osteogenic medium, and the ionic products (Ca and Si) released from wollastonite might contribute to this advantage. It is also suggested that the osteogenic differentiation of the hBMSCs can be affected by adjusting the wollastonite content in the composite scaffolds.