The utility model relates to a four-bar linkage mechanism teaching demonstration prop, which comprises a crank I (1), a crank II (4), a connecting rod (2), a motor (6) and a base (7), wherein the motor is arranged below the base, and a shaft of the motor is located above the base. The four-bar linage mechanism teaching demonstration prop is characterized by further comprising two parallel grooves arranged on the base (7), a bracket (5) with a groove, a guide block (8), a disk (11), a slideway (12) and a sliding block (10). The assemblies form different four-bar linkage mechanism teaching demonstration props through different connection modes. The four-bar linkage mechanism teaching demonstration prop can display a four-bar linkage mechanism visually, and can also acquire an accurate solution through a sensor. In addition, the size of the mechanism is changeable, thereby having high flexibility.