PURPOSE: To suppress the cost of the device by simplifying the execute electrostatic charge to desired potential and to enhance the uniformity of the electrostatic charge.

CONSTITUTION: The contact type electrostatic charge device is provided with a potential sensor 403 which detects the surface potential of a photosensitive body 101, a control part 402 which outputs a voltage which is previously set to the inversion terminal of an operation amplifier 404 according to the detected result of the sensor 403, a power source 405 which outputs a prescribed voltage to the noninversion terminal of the amplifier 404, a variable resistance 401 which adjusts a resistance value according to the output of the amplifier 404 and an electrostatic charge roller 102 on which the voltage from the power source 103 is impressed by being adjusted by the resistance 401.