Abstract. This paper investigates the motion of the Maxwell pendulum in a uniform gravitational field. In addition, using the Maxwell pendulum, the theoretically and experimentally found values were compared and analyzed. The threads on which the axis and the disk of the pendulum have been suspended are assumed to be weightless and inextensible, and the characteristic linear size of the disk is assumed to be small compared to the lengths of threads. Theoretical values of the nonlinear properties are derived using the conservation of energy and with respect to small deviations of the threads from the vertical.