To provide an antilithic material excellent in high slipperiness and antilithic property, which is used ideally for endoscopes, catheters, stents, sheaths, guide wires and the like and has a higher slipperiness to enable not only reducing of damage to celomic endothelium but also prevention of bacterial infection and adhesion of calculus in retention within a body cavity.

This antilithic material comprises a polymer which is produced by graft polymerization of a polyalkyleneoxide chain with the degree of polymerization of 10 or more on a straight chain main polymer. The polyalkyleneoxide herein used is preferably polyethyleneoxide. The graft polymer herein used has a polyalkyleneoxide chain and the density thereof is 0.0001 mol-0.5 mol per 1 mol of the repeating unit of the straight chain main polymer.