The invention discloses a unicycle device capable of achieving all-directional movement decoupling. A lateral balancing adjustment mechanism is arranged in a base body. The lateral balancing adjustment mechanism comprises upper and lower side direction balancing frameworks and upper and lower side direction balancing rotary discs which are separately arranged based on the upper and lower side direction balancing frameworks. The upper and lower-side balancing rotary discs rotate at a high speed, and the upper and lower side direction balancing frameworks relatively rotate in a small angle. A pitching balancing adjustment mechanism is arranged at the bottom of the base body, and comprises a single wheel and a fork. A turn taking adjustment mechanism is arranged on the top of the base body, and comprises left and right turn taking adjustment frameworks based on a support rack and left and right turn taking adjustment rotary discs which are separately arranged based on the left and right turn taking adjustment frameworks. The left and right turn taking adjustment rotary discs rotate at a high speed and the left and right turn taking adjustment frameworks relatively rotate in a small angle. According to the invention, the unicycle device is decoupled on pitching, side direction and turn taking mathematic models, so difficulty in controlling movement of the unicycle body is greatly reduced.