The present invention provides a resist composition, including: (A) a sulfonium salt containing an anion and a cation, the cation including a partial structure shown by the following general formula (A1); and (B) a polymer compound containing a repeating unit shown by the following general formula (B1). The present invention provides a resist composition that causes few defects and is excellent in lithography performance, having regulated acid diffusion, in photolithography using a high energy beam as a light source, and a resist patterning process using this resist composition.