To dispense with after-treatment by cooling a wire saw and by removing a chip, without using water, and to prolong a life of the wire saw.

A dry ice particle is blown at high velocity from a nozzle 21 of a dry ice blowing means 2 to the wire saw 10, the chip deposited on the wire saw 10 is removed, and the wire saw is cooled, in a wire saw cutting method for cutting a cutting object, by winding the wire saw 10 onto the cutting object, and by running-driving the wire saw 10 by a wire saw drive unit 1. The removed chip is sucked by a dust collector 3 and is treated not to be scattered and lost to the periphery.