The present invention addresses the issue of providing a heat treatment system and a heat treatment method whereby the inner circumference of a cylindrical workpiece can be reliably cooled regardless of the dimensions or shape of the workpiece and productivity can be improved, during quenching of the inner circumference of the cylindrical workpiece. The present invention has: rotating devices 18, 19 that rotate the cylindrical workpiece 11: holding members 181, 191 that hold the cylindrical workpiece 11 at a prescribed position; a heating member 16 that heats the cylindrical workpiece 11 from the inner circumferential surface side; a cooling device 17 that injects cooling fluid and cools the cylindrical workpiece 11 from the outer circumferential surface side; and a injecting device 34 provided at a position separated from the cooling device 17 and which inject the cooling fluid.