Abstract: A crosslinked ethylene-olefin copolymer foam and a method for the production thereof are disclosed. The foam having a gel content of 70 to 99%, an apparent density of 0.2 to 0.02 g/cm3, 25% compression set at 40° C. of 0.1 to 20.0%, 25% compression hardness of 0.1 to 1.0 kgf/cm2, and Asker C type surface hardness of 3 to 40 is foamed from a copolymer of ethylene and &agr;-olefin having 3 to 18 carbon atoms, the copolymer having a melt flow rate (MFR) of 0.1 to 100 g/10 minutes, a critical shear rate (CSR) satisfying the equation: log[CSR]≦2.48+0.500×log[MFR], a density of 0.860 to 0.935 g/cm3, a Q value determined by the size exclusion chromatography (SEC) of 1.5 to 4, and an extrapolated end temperature of melting (Tem) of 65° C. to 130° C.