Abstarct: In this thesis, we study the designing of fuzzy controllers for path planning of multiple mobiling robots in dynamic unknown environments . By unknown environment, we mean the lack of a map of the entire environment, and by being dynamic; we mean the presence of moving obstacles in the environment. Our main goal is to plan the movement of a group of robots from the original dynamic mode to the final state while avoiding collisions , static and dynamic obstacles. We assume that none of the robots have complete information about the environment and do not share their knowledge with each other. So, finding the optimal route is not always possible and finding a good path (close to optimal) is valuable. In this thesis, we first formulate the problem as a linear programming. Then, using a fuzzy controller as a mexta-heuristic method, we plan the routing of a robot in an unknown static environment. In the following, we extend the previous state and outline the simultaneous routing of several robots in an unknown dynamic environment using a fuzzy controller. As well, we propose an algorithm for optimizing the multi-objective robot path planning in dynamic environments, and we will show that this approach is capable of finding the near-optimal solution very fast.