To provide a roll blanket dryer which can efficiently dry print ink solvent that permeates a blanket of a blanket roll during printing process being conducted on an off-set printing machine by air flow flowing while forming turbulence around the surface of the blanket, and also can prevent air containing printing ink solvent vapor from discharging into the ambient surrounding.

The blanket roll 1 includes: a blanket 2; a dry block 3 provided outside the blanket 2, including a slit-like suction port 6 and extending in a direction parallel to the roll axis center direction in the center of a curvature-shaped direction; a flow channel-forming surface 4 of the curvature-shape, extending in the parallel direction to the roll axis center of the blanket roll 1 in accordance with the width size of the blanket 2 and having its bottom surface running along the outer circumference surface of the blanket 2; and an air flow channel 5 formed between the flow channel-forming surface 4 and the outer circumference surface of the blanket 2. The flow channel-forming surface 4 has a turbulence forming groove 11 extending in the parallel direction to the axial center of the roll. When a sucking means 9 reduces the pressure of the suction port 6 to allow air suction ports 5a on both sides of the air flow channel 5 to let air 12 flow toward the suction port 6, the turbulent forming groove 11 generates swirl of turbulence vertical to the air flow direction, thereby: stirring the air 12 in the proximity of the outer circumference surface of the blanket 2; and constantly reducing the solvent vapor pressure in the proximity of the surface of the blanket 2 to accelerate the solvent vaporization.