An algorithm based on immune network model for an unknown environment is proposed to accomplish multi-robotspsila exploration task fast for an unknown environment. Each local environment condition sensed by the robots is considered as antigen while robot is regarded as antibody respectively. Each robot works independently according to the antigen information. The coordination of the robots can be realized by utilizing the interactions among antibodies and stimulus from antigen. The system carries out the exploration of unknown environment with the combination of robotpsilas independence and coordination. Simulation experiment was carried out. In the simulation, the exploration algorithm based on immune network model is compared with Market algorithm. Simulation results prove that robots collaboration extent is improved obviously. Moreover exploration efficiency is improved greatly. With the obstacle density change, the exploration time is analyzed also.