Provided is a surface-treated calcium carbonate that can make a vinyl chloride-based resin composition less colorable in a weathering test and excellent in impact strength. The surface-treated calcium carbonate is a calcium carbonate subjected to treatment with a surface treatment agent in which a proportion of saturated fatty acid contained in a fatty acid is 85% by mass or more, and has a content of elemental iron of 0.01% by mass or less, a content of elemental zinc of 0.1 to 2% by mass introduced by the treatment with the surface treatment agent, and a BET specific surface area of 5 to 30 m2/g.