PURPOSE: A roll operation testing device is provided to reduce unexpected errors on the repaired roll and block by estimating the error states through an inspection step. CONSTITUTION: A roll operation testing device comprises a holder, a drive motor(2), and a testing device manipulation part(1). The holder comprises a roll block settling frame(3), an upper fixing plate(4), an adjusting gap frame, a screw jack mount base, a screw jack, and a screw jack connection stick(10). The roll block settling frame is protruded on the front and rear side of the bottom part. The upper fixing plate covers the upper end of the left and right roll block settling frame and is fixed to the roll block settling frame using the fixing screw. The adjusting gap frame is attached to the roll block settling frame. The screw jack is installed on the screw jack mount base of the back and front surfaces. The screw jack connection stick fixes the front and rear surface screw jacks.