A composition for forming a superfine pattern, comprising pure water and a water-soluble resin represented by the following formula: -X p -Y q -Z r - wherein X, Y and Z are repeating units of respectively; p, q and r are numbers of polymerization ratios of said repeating units X, Y and Z, respectively, provided that they satisfy the conditions of 0.60≤p+r≤0.95 and 0,05≤q≤0.40 and that each repeating unit may combine with each other either randomly or to form a block; a in said repeating unit X or Y is an integer of 0 or 1; L in said repeating unit Y is a divalent linking group selected from the group consisting of - N=CH-, - NH-CHR 0 -, - NH-CH 2 -CHR 0 - and - NH-CHR 0 -CH 2 - where R 0 is selected from the group consisting of -H, -CH 3, -COOH, -CH 2 COOH, -CH(CH 3) 2 and -COOC 2 H 5; Ar in said repeating unit Y is a group represented by the following formula: where b is an integer of 0 to 5; c is an integer of 0 to 5-b; R 1 is an organic group comprising elements selected from the group consisting of carbon, nitrogen, oxygen and fluorine; in the case where b is 2 or more, two R 1 s may combine with each other to form a ring structure; and R 2 is an acid group selected from the group consisting of - COOH, -CH 2 COOH, -CH(CH 3)COOH, -OCH 2 COOH, -SO 3 H and -OH; said repeating unit Y contains at least one acid group; and each of said repeating units X and Y may be a combination of repeating units having different structures, respectively. X, Y and Z are repeating units of respectively; p, q and r are numbers of polymerization ratios of said repeating units X, Y and Z, respectively, provided that they satisfy the conditions of 0.60≤p+r≤0.95 and 0,05≤q≤0.40 and that each repeating unit may combine with each other either randomly or to form a block; a in said repeating unit X or Y is an integer of 0 or 1; L in said repeating unit Y is a divalent linking group selected from the group consisting of - N=CH-, - NH-CHR 0 -, - NH-CH 2 -CHR 0 - and - NH-CHR 0 -CH 2 - where R 0 is selected from the group consisting of -H, -CH 3, -COOH, -CH 2 COOH, -CH(CH 3) 2 and -COOC 2 H 5; - N=CH-, - NH-CHR 0 -, - NH-CH 2 -CHR 0 - and - NH-CHR 0 -CH 2 - where R 0 is selected from the group consisting of -H, -CH 3, -COOH, -CH 2 COOH, -CH(CH 3) 2 and -COOC 2 H 5; Ar in said repeating unit Y is a group represented by the following formula: where b is an integer of 0 to 5; c is an integer of 0 to 5-b; R 1 is an organic group comprising elements selected from the group consisting of carbon, nitrogen, oxygen and fluorine; in the case where b is 2 or more, two R 1 s may combine with each other to form a ring structure; and R 2 is an acid group selected from the group consisting of - COOH, -CH 2 COOH, -CH(CH 3)COOH, -OCH 2 COOH, -SO 3 H and -OH; said repeating unit Y contains at least one acid group; and each of said repeating units X and Y may be a combination of repeating units having different structures, respectively. where b is an integer of 0 to 5; c is an integer of 0 to 5-b; R 1 is an organic group comprising elements selected from the group consisting of carbon, nitrogen, oxygen and fluorine; in the case where b is 2 or more, two R 1 s may combine with each other to form a ring structure; and R 2 is an acid group selected from the group consisting of - COOH, -CH 2 COOH, -CH(CH 3)COOH, -OCH 2 COOH, -SO 3 H and -OH;