A process comprising the steps of (1) sizing a warp with an aqueous solution containing a partially hydrolyzed polyvinyl acetate, having a degree of hydrolysis of 50% to 80% by mole and an average degree of polymerization of not less than 400, and an anionic surface active agent capable of solubilizing the hydrolyzed polyvinyl acetate in water or capable of raising the cloud point of the hydrolyzed polyvinyl acetate, and then weaving, (2) subjecting the woven cloth to desizing in a scouring bath, and washing the cloth, and then (3) treating the desizing and washing waste water with an agent selected from polyvalent metal salt chelate-forming agents, strong acids and cationic compounds by adding the agent to the waste water to deposit the hydrolyzed polyvinyl acetate, and separating the deposited hydrolyzed polyvinyl acetate. The sizing work efficiency is good, the weaving efficiency is high, the desizing is smooth, and the waste water treatment is easy.