A vehicle seat sliding apparatus comprising: a lower rail adapted to be fixed to a vehicle-floor; an upper rail adapted to be fixed to a seat cushion and connected to the lower rail so as to be movable with respect to the lower rail; a lock lever rotatably connected to the upper rail and adapted to engage the lower rail to selectively restrict the movement of the upper rail with respect to the lower rail; a supporting bracket fixed to the upper rail; an operating lever rotatably connected to the supporting bracket and being capable of transmitting an operating force to the lock lever to release the restriction of movement by being linked with the lock lever; and an urging member (41, 74, 76) adapted to resiliently hold the operating lever, wherein the supporting bracket includes a plate-shaped supporting wall portion which is adapted to serve as a fulcrum of rotation of the operating lever at an abutting portion with respect to an upper portion of the operating lever when the operating lever is inserted therein along the longitudinal direction of the upper rail, the operating lever is formed with a slit-like holding groove adapted to lock the urging member therein on the upper portion thereof on the side of the lock lever with respect to the supporting wall portion in terms of the longitudinal direction of the upper rail so as to extend in the direction orthogonal to the direction of insertion of the operating lever, and the supporting wall portion has a molded portion opposing an upper portion of the operating lever within the range of the holding groove in the direction orthogonal to the direction of insertion of the operating lever and having a width wider than the width of the holding groove in terms of the direction of insertion of the operating lever. a lower rail adapted to be fixed to a vehicle-floor; an upper rail adapted to be fixed to a seat cushion and connected to the lower rail so as to be movable with respect to the lower rail; a lock lever rotatably connected to the upper rail and adapted to engage the lower rail to selectively restrict the movement of the upper rail with respect to the lower rail; a supporting bracket fixed to the upper rail; an operating lever rotatably connected to the supporting bracket and being capable of transmitting an operating force to the lock lever to release the restriction of movement by being linked with the lock lever; and an urging member (41, 74, 76) adapted to resiliently hold the operating lever, wherein the supporting bracket includes a plate-shaped supporting wall portion which is adapted to serve as a fulcrum of rotation of the operating lever at an abutting portion with respect to an upper portion of the operating lever when the operating lever is inserted therein along the longitudinal direction of the upper rail, the operating lever is formed with a slit-like holding groove adapted to lock the urging member therein on the upper portion thereof on the side of the lock lever with respect to the supporting wall portion in terms of the longitudinal direction of the upper rail so as to extend in the direction orthogonal to the direction of insertion of the operating lever, and the supporting wall portion has a molded portion opposing an upper portion of the operating lever within the range of the holding groove in the direction orthogonal to the direction of insertion of the operating lever and having a width wider than the width of the holding groove in terms of the direction of insertion of the operating lever.