The substrate for artificial leathers of the invention comprises an entangled nonwoven fabric which is mainly made of bundles of polyamide microfine fibers and an elastic polymer which is impregnated into intervening spaces in the entangled nonwoven fabric. The single fiber fineness of polyamide microfine fibers is 0.2 dtex or less. The bundles of polyamide microfine fibers have an average tenacity of 3.5 cN/dtex or more and an average elongation of 60% or less. Despite its extremely low apparent specific gravity of 0.30 or less, the substrate for artificial leathers exhibits high mechanical properties as evidenced by a tear strength of 50 N/mm or more. Thus, the substrate for artificial leathers is well balanced between the mechanical properties, feel and light weight which are required particularly in sport shoes applications to an extent not conventionally attained.