Semipermeable membrane support

A semipermeable membrane support used by forming a semipermeable membrane thereon, which is a wet-laid nonwoven fabric consisting of core-sheath type conjugate fibers consisting of polypropylene as a core component and polyethylene as a sheath component, wherein

• the core-sheath type conjugate fibers are core-sheath type conjugate fibers A having an average fiber diameter of more than 9 μm to not more than 11 μm, and a content of the core-sheath type conjugate fibers A is 100 mass %,
• a Bekk smoothness and a 75° mirror surface glossiness of a coating surface on which a semipermeable member is to be formed of the semipermeable membrane support are more than a Bekk smoothness and a 75° mirror surface glossiness of a non-coating surface on an opposite side,
• the Bekk smoothness of the coating surface on which the semipermeable membrane is to be formed of the semipermeable membrane support is 1.0 to 51.0 seconds and a ratio of the Bekk smoothness of the coating surface to that of the non-coating surface is 1.3:1.0 to 1.1:1.0, and
• the 75° mirror surface glossiness in a MD direction of the coating surface of the semipermeable membrane support is 10 to 30%, the 75° mirror surface glossiness in a CD direction of the coating surface of the semipermeable membrane support is 8 to 25%, and a ratio of the surface glossiness in the MD direction of the coating surface to that of the non-coating surface is 1.0:0.9 to 1.0:0.7.