We, in this study, try to acquire cooperative behaviors of multiple robots on the basis of evolutionary robotics approach. As the cooperative task, the 3-Dimensional balancing problem is given. This problem is an example of corresponding tasks to find the appropriate movements for multiple mobile robots. Each robot agent on a flat board keeps being balanced state by using evolutionary robotics approach. The behaviors of mobile robots are calculated by corresponding neuro-controller which consists of artificial neural networks. Evolutionary computation method is applied to evolve weight values of neuro-controller. Numerical simulations are carried out by a simulator constructed based on 3-D physical engine ODE(Open Dynamic Engine). As a result of simulations, usefulness of our approach is clarified.