The invention provides a randomly turning chaotic pendulum, and relates to the field of dynamics. According to the device (the chaotic pendulum), a power supply is arranged on a base; an electromagnetis arranged in a first supporting rod which is arranged in a mode of being perpendicular to the base; a first permanent magnet is arranged at the outer side, close to the upper end of the first supporting rod, of a first arc-shaped body under a static state, and a second supporting rod is arranged at the inner side; a transparent ball body is arranged at the upper end of the second supporting rod; and energy loss of the device in a rotating process is supplemented by a magnetic interaction which is caused between a first point electromagnet and the first permanent magnet when a power supply is turned on, so that continuous random rotation is achieved. The randomly turning chaotic pendulum provided by the invention can demonstrate a chaos phenomenon more vividly; and the chaotic pendulum has a sense of layering.