A coolant temperature control apparatus for a wet saw is provided, in which a coolant temperature controller is mounted on the wet saw to heighten the temperature of the coolant to a set temperature, and thus a tile cutting work can be efficiently performed even in cold weather below zero with the work continuity heightened. The coolant temperature control apparatus for a wet saw includes a support member on which a material to be cut is arranged, an electric cutting device cutting the material arranged on the support member, a coolant supply device cooling heat generated during operation of the electric cutting device, and a coolant temperature controller heightening the temperature of coolant stored in the coolant supply device.