A new Reconfigurable Planetary Robot System (RPRS) is introduced in this paper. The locomotion mechanism, especially the static force analysis and the climbing ability for different configurations of the multiple child-robots are presented in detail. The basic configurations of two child-robots systems were given in three modes: connecting in series with arm in front or back and combining to a loop with grasper. The simulation results of these three configurations based on static analysis demonstrate that the climbing ability is closely correlated to their configurations. Compared the results, the conclusion can be obtained that the loop configuration has the best effect than others on slope climbing. The actual experiments of the child-robots system have illustrated the simulating results, and an exciting phenomenon has emerged, which shows that all the configurations can climb bigger gradient than the simulating results. The phenomenon rightly discloses the characteristic of the novel architecture of the child-robot.