To provide a novel method for coating the surface of an extended- wear contact lens.

The method for coating the surface of a material comprises (a) a step of preparing a hydrophilic telomer group of formula I [wherein T is hydroxy, epoxy, amino, 1-6C alkylamino or carboxy or a carboxy derivative; and (oligomer) is a telomer group of formula II (wherein (Alk) is a 2-12C alkylene optionally interrupted by -0- or -NH-; Q is a monovalent group in a polymerization chain reaction terminator; a and b are each an integer of 0-350; (a+b) is an integer of 2-350; and Z and Z' are each a 1,2-ethylene group bearing a hydrophilic side chain having a weight-average mol.wt. of ≥200)] and (b) a step of bonding the hydrophilic polymer covalently to the surface of the material.