Water-soluble resin composition for forming fine pattern, and method of forming fine patterns by using the same

The present invention relates to a water-soluble resin composition for forming fine patterns by carrying out coating and thermal treatment on a photoresist film forming contact hole patterns to reduce the contact hole size. Said composition includes: a water-soluble polymer represented by the following [Chemical Formula 1] and a first water-soluble solvent, wherein in the above-mentioned [Chemical Formula 1], R1, R2, R3, R4, and R6 are independently C1-30 alkyl or C3-30 cycloalkyl including hydrogen, ether group, hydroxyl group, ester group, carbonyl group, acetyl group, epoxy group, cyano group, amino group, lactone group or aldehyde group. Herein R3 is not identical to R4, and R5, R7, R8, R9, and R10 are independently hydrogen or methyl group. n is an integer of 0~5, a is a real number of 0.05~0.5, b, c, d, and e are individually a real number below 0.7, and a, b, c, d, and e satisfy the condition of a+b+c+d+e=1.