The paper presents the method of the angular orientation for a mobile robot passing obstacles in a labyrinth. A small RAM of the microcontroller is one of the drawbacks in the mobile robots' control system. In order to compensate for it the authors suggest using fuzzy hierarchical system of the angular orientation of the mobile robots. An advantage of this system is a smaller number of computations. This is possible because the output information is supplied to the next level of the fuzzy hierarchical system without the use of defuzzification. The input information for the fuzzy hierarchical system of control of a mobile robot is the data, which comes from the laser and ultrasonic sensors. Proceeding from this information, the paper presents the algorithms, which allow a mobile robot to detect obstacles and bypass them. Besides, the circuits connecting the sensors to a mobile robot are shown. The second part of the paper presents the top level of the fuzzy hierarchical control system of the angular orientation of a mobile robot. A distinctive feature of the fuzzy hierarchical system is that the model difference areas are used in the defuzzification. Simulation of the fuzzy hierarchical system was realized, when hard and soft arithmetic operations were used in the fuzzy inference. The presented graphs of the results of the work of the fuzzy hierarchical system show the effectiveness of the proposed solutions. The experimental results of bypassing of the labyrinth by a mobile robot also confirmed the adequacy of the developed fuzzy hierarchical control system of the angular orientation for a mobile robot.