PURPOSE: To obtain a thawer capable of reducing the inner volume without any wasteful space by arranging plural belt conveyors extending in nearly the horizontal direction in a freezing chamber in the upper and lower parts and housing the belt conveyors therein.

CONSTITUTION: Conveyors 21, 22 and 23 are arranged in the horizontal direction with a steel frame 24 installed in a freezing chamber and cold air is lowered in a cold air passage along the sidewall of the freezing chamber with an air blast fan 52. The cold air passage is branched into three for each conveyor part with guide plates. A food to be conveyed is lightly pressed with a belt 32 so as not to slip down from a pulley 26 and further lightly pressed with a belt 33 so as not to slip down from a pulley 29.