To prevent uneven density of an image being recorded by applying a thermal head to a recording sheet with a uniform pressure.

Pair carry rollers 14 and 16 are driven by motors 24 and 26 to carry a recording sheet 12 while gripping. A system controller 22 imparts a tension to a recording sheet 12 by regulating the voltage being applied to each motor 24, 26 such that the carrying torque of the pair carry rollers on the downstream side in the carrying direction becomes larger than that of the pair carry rollers on the upstream side. At the time of recording an image, a thermal head 18 depresses the recording sheet 12 imparted with a tension and then it is moved to a recording position traversing a line connecting the positions of the recording sheet 12 being gripped by the pair carry rollers 14 and 16. When the thermal head 18 is moved to the recording position, the recording sheet 12 tries to push back the thermal head 18 by its tension. Consequently, the thermal head 18 and the recording sheet 12 are brought into press contact and an image can be recorded.