Abstract: An apparatus for mounting a front latch device to a front side of a sliding door to be closed and opened by moving in front-and-rear direction of a vehicle body comprises a mounting wall to which the front latch device is mounted by screws or bolts. The front latch device is provided with a latch body accommodating a fork member and pawl member, and first and second metal plates mounted to the latch body. The first metal plate is closely adhered onto the mounting wall, and the second metal plate has boss portions to be engaged with ends of the screws or bolts. The latch body sandwiched between the first and second plates. The mounting wall is parallel to a direction in which the front latch device moves.