PURPOSE: To homogeneously dry warp sheets by disposing an air flow-generating unit and a dryness-detecting sensor in a pre-drying process for each sized warp sheet and controlling the air flow in correspondence to the dryness.

CONSTITUTION: In a sizing and drying machine in which each sized warp sheet is passed through a pre-drying process comprising a pair of plural drying cylinders for preliminarily drying the warp sheet and in which the plural pre- dried warp sheets are combined into a sheet and subsequently subjected to a finish drying process with a finish drying cylinder, an air flow-generating unit and a dryness-detecting sensor are disposed for each pre-drying unit. The dryness of each warp sheet is detected by measuring the moisture content, temperature, tensile strength, etc., of the warp sheet and the volume or temperature of the air flow generated from the air flow-generating unit is simultaneously controlled on the basis of the detection result so as to eliminate the difference between the respective warp sheets.