A new two-way trimming circuit for bandgap reference is presented in this paper. This method is different from the one-way trimming used before, which makes the two-way trimming come true by the two-way resistance controlled by MOS switch. It can counteract the effect of production process very well. Under the simulation environment with 0.35um CMOS technology, results show that this circuit can greatly reduce the influence of technology fluctuation for the output voltage. Before trimming, the output voltage offset can arrive -5%~+7% under the worst-technology-case.This method that won’t consume additional power can promote output stability within ±2% after trimming.