Based on improving the four order Adams-Bashforth-Moulton（shorten as ABM）predictor-corrector methods，we got the modifier formula of the ABM methods. Using Matlab language，we compared the solutions of those methods with the exact solution of a numeric example. The results said the error of the modifier formula of the four order ABM predictor-corrector is smaller than that of the the four order ABM predictor-corrector.