An object is to provide a thermal transfer printer having an inexpensive configuration and capable of making a tension given to an ink ribbon as constant as possible, even when a secular change and an environmental change occur in a DC motor used as a supply motor and a winding motor. A supply motor control unit controls a supply motor of an ink ribbon supply unit. A winding motor control unit controls a winding motor of an ink ribbon winding unit. A remaining amount detection unit detects a remaining amount of an ink ribbon. A variable calculation unit acquires parameters for an armature current, an applied voltage, and a rotational speed of each of the supply motor and the winding motor, and calculates variables to be used for controlling the supply motor and the winding motor on the basis of the acquired parameters.