A polyolefin-based resin film comprising a polyolefin-based resin composition, wherein the polyolefin-based resin composition comprises at least a propylene-a olefin random copolymer and the following 1) to 5) are satisfied, and which is characterized in that the polyolefin-based resin film further fulfills the following 6): 1) a content of an olefin-based block copolymer is 0 to 2 parts by weight based on 100 parts by weight of the propylene-a olefin random copolymer in the polyolefin-based resin composition; 2) a content of an olefin-based copolymeric elastomer resin is 0 to 2 parts by weight based on 100 parts by weight of the propylene-a olefin random copolymer in the polyolefin-based resin composition; 3) a content of a propylene homopolymer is 0 to 40 parts by weight based on 100 parts by weight of the propylene-a olefin random copolymer in the polyolefin-based resin composition; 4) the polyolefin-based resin film exhibits a thermal shrinkage rate after heating at 120°C for 30 minutes of 25% or less in a direction in which the thermal shrinkage rate after heating at 120°C for 30 minutes is larger between a longitudinal direction and a lateral direction of the polyolefin-based resin film; and 5) a planar orientation coefficient ΔP calculated from a refractive index of the polyolefin-based resin film is 0.0100 or more and 0.0145 or less, 6) an orientation coefficient ΔNx in the longitudinal direction of the polyolefin-based resin film is 0.010 or more, the orientation coefficient ΔNx being calculated from the following formula : ΔNx = Nx − Ny + Nz / 2 wherein Nx is a refractive index in the longitudinal direction, Ny is a refractive index in a direction perpendicular to the longitudinal direction, and Nz is a refractive index in a plane direction. 1) a content of an olefin-based block copolymer is 0 to 2 parts by weight based on 100 parts by weight of the propylene-a olefin random copolymer in the polyolefin-based resin composition; 2) a content of an olefin-based copolymeric elastomer resin is 0 to 2 parts by weight based on 100 parts by weight of the propylene-a olefin random copolymer in the polyolefin-based resin composition; 3) a content of a propylene homopolymer is 0 to 40 parts by weight based on 100 parts by weight of the propylene-a olefin random copolymer in the polyolefin-based resin composition; 4) the polyolefin-based resin film exhibits a thermal shrinkage rate after heating at 120°C for 30 minutes of 25% or less in a direction in which the thermal shrinkage rate after heating at 120°C for 30 minutes is larger between a longitudinal direction and a lateral direction of the polyolefin-based resin film; and 5) a planar orientation coefficient ΔP calculated from a refractive index of the polyolefin-based resin film is 0.0100 or more and 0.0145 or less, 6) an orientation coefficient ΔNx in the longitudinal direction of the polyolefin-based resin film is 0.010 or more, the orientation coefficient ΔNx being calculated from the following formula : ΔNx = Nx − Ny + Nz / 2 wherein Nx is a refractive index in the longitudinal direction, Ny is a refractive index in a direction perpendicular to the longitudinal direction, and Nz is a refractive index in a plane direction. <EOS>