The invention relates to polydimethylsiloxane which is provided with an initiator at the surface, and is the silicon-hydrogen bonding cross-linked polydimethylsiloxane, of which the surface contains 0.01 to 1At percent 2-bromine-2-methyl propioric acid 10-undecene ester. The material is formed by mixing a polymer precursor, a cross-liner and the initiator with olefinic end in the weight ratio of 10: 1: 4-0.01 and placing for 6 to 24 hours. The polydimethylsiloxane with the initiator at the surface which is provided by the invention further modifies a function layer on the surface by triggering the polymerization reaction on the surface, so the polydimethylsiloxane can be applied on biocompatible, organic solvent compatible and thermal sensitive materials. The invention uses the simple and convenient method to realize the universal, permanent, diverse and functional surface modified polydimethylsiloxane.