Vibration analysis of gantry crane system subjected to swinging motion of payload by considering the flexibility of crane framework and hoist cable is presented in this study. The equations of motion of such a system are coupled dynamic problem, where the dynamic model is obtained by modeling the dynamics of crane framework using finite element method and dynamics of a pendulum-like swinging motion of payload by Lagrange's equations. The coupled equations of motion are solved numerically using a combinational direct integration technique, namely Newmark-β and fourth-order Runge-Kutta method simultaneously. Numerical results show that the flexibility of crane framework and hoist cable has significant effect on the dynamics of gantry crane system. © 2011 Asian Network for Scientific Information.