Provided are methods for surface-modifying a rubber vulcanizate and surface-modified elastic bodies, which can cost-effectively provide a variety of functions, including sliding properties, liquid leakage resistance, and protein adsorption resistance. Included is a method for surface-modifying a rubber vulcanizate as a modification target, the method including: step 1 of forming polymerization initiation points A on the surface of the modification target； step 2 of radically polymerizing a monomer starting from the polymerization initiation points A to grow polymer chains； and step 3 of adding a silane compound to the surfaces of the polymer chains, followed by reaction with at least a fluoroalkyl group-containing silane compound to form modified polymer chains.
