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,
• wherein the resin component (A1) has a constitutional unit (a01) represented by General Formula (a01-1) and a constitutional unit (a02) represented by General Formula (a02-1),
• wherein 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, Yax01 represents a single bond or a divalent linking group, Ax represents a sulfonyl group or a sulfoxide group, Rax01 represents an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a halogen atom, or a halogenated alkyl group having 1 to 6 carbon atoms, and s0 represents an integer of 0 to 6, and v0 represents an integer of 0 to 6, provided that 1≤s0+v0≤6 and u0≤s0+v0,
• wherein 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, Va0 represents a divalent hydrocarbon group which may have a substituent, na0 represents an integer of 0 to 2, Ra00 represents an acid-dissociable group represented by General Formula (a02-r2-1), Ra01 represents a hydrocarbon group which may have a substituent, Ra02 represents a hydrocarbon group which may have a substituent, Ra01 and Ra02 may be bonded to each other to form a ring structure, Ya0 represents a quaternary carbon atom, Ra031, Ra032, and Ra033 each independently represents a hydrocarbon group which may have a substituent, two or more of Ra031, Ra032, and Ra033 may be bonded to each other to form a ring structure, and * represents a bond.