Aim To investigate the effects of basic fibroblast growth factor (bFGF).newborn calf serum (NCS) and heparin on rat vascular smooth muscle cells (VSMC) migration in vitro.Methods Cultured rat VSMC were starved for 24 h and then scraped with a single-edged razor blade. Cell migration in vitro was assayed by measuring the maximal linear distance of cell nucleus from the cut edge with a calibrated ocular micrometer after cells were incubated with different does of NCS or bFGF or heparin for 24 h, 48 h. 72 h.Results The migration distances of VSMC stimu-lated with various concentrations of NCS or bFGF were significantly longer than those of the control group), respectively(p>0. 001 or P<0. 01). But the migration distances of VSMC treated by heparin and NCS were shorter than the control (20% of NCS)dis-tances. All the effects were in a dose-dependent fash-ion.Conclusion NCS and bFGF could stimulate VSMC migration significantly. However, heparin markedly inhibited VSMC migration induced by NCS.