Folding simulations often get biased by flaws in force field employed.In this work, we propose a novel formula based atomic charge polarization model to surmount the homogeneous approximation in traditional AMBER force field.With this charge model, we study the folding of a short helical peptide 2I9M using replica exchange molecular dynamics, and compare the result with AMBER03 charge.In AMBER03 simulation, we find a decoy structure which has nearly the same free energy as the folded structure, which makes the simulation less reliable.