To investigate the effects of basic fibroblast growth factor (bFGF) on intracellular free Ca 2+ of heating injury, and observe the relationship between mitogen activated protein kinases(MAPKs)signal pathways and Ca 2+ mobilization. Cultured human fibroblasts were heated at 45?C for 10min, then divided into four groups :①basic fibroblast growth factor (10ng/ml) treatment; ②preincubated cells with PD98059 (10?mol/L) for 30 min followed by bFGF (10ng/ml); ③preincubated cells with SB203580 (10?mol/L) for 30min followed by bFGF (10ng/ml); ④preincubated cells with PD98059 (10?mol/L) and SB203580 (10?mol/L) for 30min followed by bFGF (10ng/ml). The cells were incubated with fluorescence Ca 2+ dye fluo 3/AM at 37 C for 30min, then measured by using laser scanning confocal microscope. The results showed fluorescent intensity of fibroblast heating injury was weak, the concentration of intracellular free Ca 2+ increased after stimulation with bFGF treatment. PD98059 and SB203580 could induce calcium oscillation. A rapid decrease of fluorescent intensity was observed after cells were preincubated with PD98059 and SB203580 at the same time. bFGF induced an increase of cytoplasmic and intracellular free Ca 2+ concentrations. It is suggested that MAPKs signaling pathway has a feedback regulation for free Ca 2+ mobilization.