Abstract: A fixing device includes a rotatable fixing member, a rotatable pressuring member and an electric charge supplying device. The fixing member contacts a recording medium having a toner image and heats the recording medium. The pressuring member pressures the recording medium between the fixing member and the pressuring member. The electric charge supplying device electrically discharges electric charges with same polarity as toner and supplies the electric charges to the fixing member. An output current value electrically discharged by the electric charge supplying device is adjusted on the basis of a toner charged amount of the toner image. When the toner charged amount is equal to or more than a threshold value, the output current value is set to a normal current value. When the toner charged amount is less than the threshold value, the output current value is set to a current value higher than the normal current value.