Abstract: Based on lattice model,Monte Carlo simulations have been taken to explore the performances of two component chain molecules for competitive adsorption on solid surface.The dynamic process of adsorption before equilibrium is traced.The segment distribution and configuration distribution of two unequal length chain molecules at equilibrium are obtained.It is found that the shorter chains are preferably adsorbed due to its quick diffusion to the surface at the beginning of simulation,however,the adsorbed shorter chains are displaced by the longer ones later,which can enhance the system with further stability.