Ab s t r a c t. The importance of finding a path for autonomous moving robots is indispensable, because the successful achievement of the target location depends on the solution of this problem. There are a large number of different methods of finding the way, which differ in the accuracy of work, speed, the need for additional equipment. Underground environments, such as mines and tunnels, differ from other structures and open space, and therefore, require different approach when performing pathfinding, as narrow, curved passages and heterogeneous structure could render some of the pathfinding methods ineffective. However, methods based on rapidly exploring random trees (RRT) maintain their effectiveness because they are unaffected by the complexity of the environment. In this article presented a comparison of the three RRT-based methods: RRT, RRT-connect and RRT*. K e ywor d s : robot; pathfinding; autonomy; RRT.