Resist underlayer film-forming composition

A resist underlayer film-forming composition for lithography, comprising:

• a polymer that has a structure of Formula (1a), Formula (1b), or Formula (2) below on an end of the polymer, and
• an organic solvent:
• (where R1 is a hydrogen atom or a methyl group;
• each of R2 and R3 is independently a hydrogen atom, a linear or branched hydrocarbon group having a carbon atom number of 1 to 6, an alicyclic hydrocarbon group, a phenyl group, a benzyl group, a benzyloxy group, a benzylthio group, an imidazole group, or an indole group;
• each of the hydrocarbon group, the alicyclic hydrocarbon group, the phenyl group, the benzyl group, the benzyloxy group, the benzylthio group, the imidazole group, and the indole group optionally has at least one of a hydroxy group and a methylthio group as substituent(s);
• R4 is a hydrogen atom or a hydroxy group;
• Q1 is an arylene group;
• v is 0 or 1;
• y is an integer of 1 to 4;
• w is an integer of 1 to 4;
• x1 is 0 or 1;
• and x2 is an integer of 1 to 5).