Resist composition and method of forming resist pattern

A resist composition generating an acid upon exposure and having solubility in a developing solution, which is changed by action of an acid, the resist composition comprising:

• a resin component (A1) having solubility in a developing solution, which is changed by action of an acid;
• and
• an acid generator component (B) generating an acid upon exposure,
• wherein the resin component (A1) has a constitutional unit (a01) derived from a compound represented by General Formula (a01-1) and a constitutional unit (a02) derived from a compound represented by General Formula (a02-1), and
• the acid generator component (B) is a compound (B1) having an anion moiety and a cation moiety:
• wherein, in General Formula (a01-1), W1 represents a polymerizable group-containing group, Ct represents a tertiary carbon atom, R11 represents an unsaturated hydrocarbon group which may have a substituent, R12 and R13 each independently represent a linear or branched saturated hydrocarbon group which may have a substituent, provided that a carbon atom at an α-position of Ct constitutes a carbon-carbon unsaturated bond;
• in General Formula (a02-1), W2 represents a polymerizable group-containing group, Wa2 represents an aromatic hydrocarbon group, part or all of hydrogen atoms which the aromatic hydrocarbon group has may be substituted with a substituent other than a hydroxy group, W2 and Wa2 may form a condensed ring, and n2 represents an integer in a range of 1 to 3.