A porous body for medical use which has a first surface and a second surface opposite to each other, and which comprises a first polymer material and a second polymer material, wherein (a) a Young's modulus of the first polymer material is lower than a Young's modulus of the second polymer material, (b) the first polymer material comprises at least one selected from (i) polysaccharides including cellulose, hyaluronic acid, alginic acid, chitin, chitosan, glycosaminoglycans, chondroitin sulfate, or heparin, (ii) peptides or proteins including collagen, gelatin, sericin, casein, fibrin, keratin, or fibroin, (iii) polymers or copolymers including acrylic resin, polycarbonate, polyvinyl alcohol, polyester, or polyurethane, and (iv) salts and derivatives of these, the second polymer material comprises at least one selected from a group consisting of (i) chitin, sericin, fibroin, carboxymethyl cellulose, and chitosan, and (ii) salts and derivatives of these such that absorbability of the first polymer material with respect to phosphate buffered saline is greater than absorbability of the second polymer material with respect to phosphate buffered saline, (c) a composition of the porous body in a first region and a composition of the porous body in a second region are different from each other, and a ratio of a mass of the second polymer material to a mass of the first polymer material in a composite fiber of the first region is smaller than a ratio of a mass of the second polymer material to a mass of the first polymer material in a composite fiber of the second region, and (d) a distance between the first region and the first surface is shorter than a distance between the second region and the first surface, wherein the porous body comprises: a first surface layer that is porous and is arranged on a surface of the porous body on a first surface side; and a support layer that is porous and is arranged on a second surface side of the first surface layer to support the first surface layer, wherein the first region is arranged on at least a part of the first surface layer, and the second region is arranged on at least a part of the support layer, and wherein each of the first surface layer and the support layer has a web of the composite fiber that comprises the first polymer material and the second polymer material. (a) a Young's modulus of the first polymer material is lower than a Young's modulus of the second polymer material, (b) the first polymer material comprises at least one selected from (i) polysaccharides including cellulose, hyaluronic acid, alginic acid, chitin, chitosan, glycosaminoglycans, chondroitin sulfate, or heparin, (ii) peptides or proteins including collagen, gelatin, sericin, casein, fibrin, keratin, or fibroin, (iii) polymers or copolymers including acrylic resin, polycarbonate, polyvinyl alcohol, polyester, or polyurethane, and (iv) salts and derivatives of these, the second polymer material comprises at least one selected from a group consisting of (i) chitin, sericin, fibroin, carboxymethyl cellulose, and chitosan, and (ii) salts and derivatives of these such that absorbability of the first polymer material with respect to phosphate buffered saline is greater than absorbability of the second polymer material with respect to phosphate buffered saline, (c) a composition of the porous body in a first region and a composition of the porous body in a second region are different from each other, and a ratio of a mass of the second polymer material to a mass of the first polymer material in a composite fiber of the first region is smaller than a ratio of a mass of the second polymer material to a mass of the first polymer material in a composite fiber of the second region, and (d) a distance between the first region and the first surface is shorter than a distance between the second region and the first surface, a first surface layer that is porous and is arranged on a surface of the porous body on a first surface side; and a support layer that is porous and is arranged on a second surface side of the first surface layer to support the first surface layer, wherein the first region is arranged on at least a part of the first surface layer, and the second region is arranged on at least a part of the support layer, and wherein each of the first surface layer and the support layer has a web of the composite fiber that comprises the first polymer material and the second polymer material.