For modular and reconfigurable robots, it is very difficult to design effective controllers due to diverse configurations. Thus, a distributed adaptive sliding mode controller is proposed in this paper to satisfy the concept of modular software. Based on geometric formulation for the dynamics of rigid body, a robot dynamics system can be divided into some subsystems by a decomposing algorithm, and then an adaptive sliding mode controller is designed for each subsystem to handle the modeling uncertainty. These subsystem controllers together constitute a modular control network to achieve stable and reliable motion of a modular and reconfigurable robot. Finally, simulation results show the validity of the proposed distributed adaptive sliding mode controller.