Resist composition and method of forming resist pattern

A resist composition which generates an acid upon exposure and exhibits changed solubility in a developing solution under action of acid, the resist composition comprising:

• a resin component (A1) exhibiting changed solubility in a developing solution under action of acid;
• and
• a compound (D0) represented by General Formula (d0),
• wherein the resin component (A1) contains a polymer compound having a constitutional unit (a01) represented by General Formula (a01-1):
• wherein Rd0 represents a monovalent organic group;
• Xd0 represents —O—, —C(═O)—, —O—C(═O)—, —C(═O)—O—, —S—, or —SO2—;
• Ydx0 represents a single bond or a divalent hydrocarbon group which may have a substituent;
• Rd001 and Rd002 each independently represent a hydrogen atom, a fluorine atom, or an alkyl group;
• Rd003 and Rd004 each independently represent a hydrogen atom or a fluorine atom;
• nd1 represents 0 or 1;
• Mm+ represents an m-valent organic cation;
• and m represents an integer of 1 or more;
• wherein, in General Formula (a01-1), R represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms;
• Va01 represents a divalent hydrocarbon group which may have an ether bond;
• na01 represents an integer of 0 to 2;
• and Ra00 represents an acid-dissociable group represented by General Formula (a01-r-1), and wherein, in General Formula (a01-r-1), Ra001 to Ra003 each independently represents a chain alkyl group which may have a substituent or a monocyclic alicyclic hydrocarbon group which may have a substituent, and in a case where Ra002 and Ra003 represent a chain alkyl group which may have a substituent, Ra002 and Ra003 may be bonded to each other to form a monocyclic alicyclic hydrocarbon group;
• and * represents a bonding site.