A simple approximate method was used to give approximate solutions for dropping shock response of cubic nonlinear packaging system. In order to obtain the accuracy of the solutions, a novel solution combining approximate method with energy method was proposed, the maximum dropping shock response acceleration and displacement of the system were obtained with energy method, and the approximation solution was corrected. Compared with the results of Runge-Kutta method, the results showed that the relative error of acceleration peak value and displacement peak value of dropping shock response was less than 0.1%, and the relative error of extended period of dropping shock was less than 2%. This study provides a simple and effective method for the dropping shock response analysis of nonlinear packaging system.