The study was directed at the development of durable press finishing of cotton fabrics by examining the use of formic acid as a catalyst for both mealamine formaldehyde and dimethylol dihydroxy ethylene urea instead of hydrochloric acid and magnesium chloride used for them, respectively, in the normal we-fixation process. The polycondensation reaction rate of melamine formaldehyde within the cotton fiber was also investigated. The results indicate that the characteristics of cotton fabrics finished in the one bath wet-fixation process are superior to those in the normal wet-fixation process.