A decurling device includes a first frame, a second frame, a decurling unit that decurls a sheet, and a level adjustment mechanism that is capable of adjusting an inclination of the decurling unit. The decurling unit includes a housing provided with a first support part and a second support part supported by the first frame and a third support part and a fourth support part supported by the second frame, paired support rollers, an endless belt, and a decurling roller. The level adjustment mechanism adjusts, in the vertical direction, a position of one of the first support part, the second support part, the third support part, and the fourth support part in the housing to adjust the inclination of the decurling unit in the vertical direction such that the paired support rollers extend in the first direction.