Objective To investigate the effect of tetramethylpyrazine pretreatment on the expression of cfos and heat shock protein (HSP70) during hypoxia-reoxygenation (H/R) in cultured fetal rat hippocampal neurons. Methods After the neurons were cultured and identified, they were randomly divided into 5 groups ( n = 24each): control group (group C), H/R group, and low, median and high concentration of tetramethylpyrazine pretreatment groups (group L, M and H). The neurons were exposed to 2 h of hypoxia followed by 24 h of reoxygenation. Tetramethylpyrazine was added with the final concentrations of 60, 200 and 800 μg/ml in group L, M and H respectively, and then the neurons were incubated for 1 h before H/R. The apoptosis rate, cell viability and expression of c-fos and HSP70 were detected. Results The cell viability was significantly lower, while the apoptosis rate was significantly higher in group A/R, L and H than in group C (P ＜0.01). The cell viability and HSP70expression were significantly higher, while the apoptosis rate and c-fos expression were significantly lower in group L, M and H than in group A/R, and in group M and H than in group L (P＜ 0.05). The cell viability and HSP70expression were significantly lower, while the apoptosis rate and c-fos expression were significantly higher in group H than in group M ( P ＜ 0.01 ).Conclusion The mechanism by which tetramethylpyrazine pretreatment inhibits the apoptosis in cultured fetal rat hippocampal neurons during H/R may be related to the dowm-regulation of c-fos expression and up-regulation of HSP70 expression.