There is disclosed a resist patterning process with a minimum line width of 65 nanometers or less may be formed by using a resist composition containing a polymer, as a base polymer of a chemically-amplified resist composition, composed of a styrene unit whose hydroxyl group is protected by an acid labile group, and an indene unit, and/or an acenaphthalene unit, wherein the polymer has the weight-average molecular weight of 4,000 to 7,000, and in particular, 4,500 to 5,500. One of the currently existing problems to be solved is the line edge roughness. To solve this problem by an acid-generator and a basic compound, there is a problem of the trade-off relationship with a resolution power. There can be provided a resist composition having a high resolution containing a base polymer such as hydroxystyrene that is protected by an acid labile group, a resist patterning process with a pattern rule of 65 nanometers or less having a reduced line edge roughness.