A sliding member (1; 1') comprising: a steel back metal layer (2; 2'); and a sliding layer on the steel back metal layer (2; 2'), the sliding layer including a porous sintered layer and a resin composition, the porous sintered layer including a Ni-P alloy phase and particles of an Fe or Fe alloy phase, the Ni-P alloy phase functioning as a binder for binding the Fe or Fe alloy phase particles with one another or binding the Fe or Fe alloy phase particles with the steel back metal layer (2; 2'); wherein the steel back metal layer (2; 2') is made of a carbon steel including 0.05 to 0.3 mass % carbon and has a structure consisting of a ferrite phase and a pearlite phase and optionally a phase of precipitates undetectable by microstructure observation at 1000-fold magnification using a scanning electron microscope; wherein a central portion in a thickness direction of the steel back metal layer (2; 2') includes not greater than 30 volume % of the pearlite phase; wherein the steel back metal layer (2; 2') includes a high pearlite phase portion (8; 8') in a surface of the steel back metal layer facing the sliding layer, the high pearlite phase portion (8; 8') including not less than 50 volume % of the pearlite phase; wherein a volume ratio of the pearlite phase in the high pearlite phase portion (8; 8') is at least twice the volume ratio of the pearlite phase in the central portion in the thickness direction of the steel back metal layer (2; 2'); wherein the high pearlite phase portion (8; 8') has a structure consisting of a ferrite phase in a form of a network and a coarse pearlite phase surrounded by the ferrite phase network, the coarse pearlite phase having an average grain size at least three times greater than an average grain size of the pearlite phase in the central portion in the thickness direction of the steel back metal layer, the high pearlite phase portion optionally including not more than 3% in the structure of bainite phase, sorbite phase, troostite phase, martensite phase, cementite phase and austenite phase; wherein an area ratio of the ferrite phase network is at least 90% of a surface of the high pearlite phase portion (8; 8') facing the sliding layer; wherein the Ni-P alloy phase consists of: 9 to 13 mass % P; optionally one or more selected from the group consisting of 1 to 4 mass % B, 1 to 12 mass % Si, 1 to 12 mass % Cr, 1 to 3 mass % Fe, 0.5 to 5 mass % Sn, and 0.5 to 5 mass % Cu; and the balance of Ni and inevitable impurities; and wherein a mass ratio of the Ni-P alloy phase in the porous sintered layer is 5 to 40 parts in relation to 100 parts of the porous sintered layer. a steel back metal layer (2; 2'); and a sliding layer on the steel back metal layer (2; 2'), the sliding layer including a porous sintered layer and a resin composition, the porous sintered layer including a Ni-P alloy phase and particles of an Fe or Fe alloy phase, the Ni-P alloy phase functioning as a binder for binding the Fe or Fe alloy phase particles with one another or binding the Fe or Fe alloy phase particles with the steel back metal layer (2; 2'); wherein the steel back metal layer (2; 2') is made of a carbon steel including 0.05 to 0.3 mass % carbon and has a structure consisting of a ferrite phase and a pearlite phase and optionally a phase of precipitates undetectable by microstructure observation at 1000-fold magnification using a scanning electron microscope; wherein a central portion in a thickness direction of the steel back metal layer (2; 2') includes not greater than 30 volume % of the pearlite phase; wherein the steel back metal layer (2; 2') includes a high pearlite phase portion (8; 8') in a surface of the steel back metal layer facing the sliding layer, the high pearlite phase portion (8; 8') including not less than 50 volume % of the pearlite phase; wherein a volume ratio of the pearlite phase in the high pearlite phase portion (8; 8') is at least twice the volume ratio of the pearlite phase in the central portion in the thickness direction of the steel back metal layer (2; 2'); wherein the high pearlite phase portion (8; 8') has a structure consisting of a ferrite phase in a form of a network and a coarse pearlite phase surrounded by the ferrite phase network, the coarse pearlite phase having an average grain size at least three times greater than an average grain size of the pearlite phase in the central portion in the thickness direction of the steel back metal layer, the high pearlite phase portion optionally including not more than 3% in the structure of bainite phase, sorbite phase, troostite phase, martensite phase, cementite phase and austenite phase; wherein an area ratio of the ferrite phase network is at least 90% of a surface of the high pearlite phase portion (8; 8') facing the sliding layer; wherein the Ni-P alloy phase consists of: 9 to 13 mass % P; optionally one or more selected from the group consisting of 1 to 4 mass % B, 1 to 12 mass % Si, 1 to 12 mass % Cr, 1 to 3 mass % Fe, 0.5 to 5 mass % Sn, and 0.5 to 5 mass % Cu; and the balance of Ni and inevitable impurities; and 9 to 13 mass % P; optionally one or more selected from the group consisting of 1 to 4 mass % B, 1 to 12 mass % Si, 1 to 12 mass % Cr, 1 to 3 mass % Fe, 0.5 to 5 mass % Sn, and 0.5 to 5 mass % Cu; and the balance of Ni and inevitable impurities; and wherein a mass ratio of the Ni-P alloy phase in the porous sintered layer is 5 to 40 parts in relation to 100 parts of the porous sintered layer.