A mounting apparatus for mounting a data storage device on a bracket includes a locating member fixed on the bracket. The bracket includes a sidewall defining a first through hole and a second through hole at a sidewall back. The sidewall defines a first fixing slot and a second fixing slot at a sidewall front. The data storage device defines a fixing hole. A fixing portion is located on a first end of the locating member corresponds to the first through hole, the second through hole and the fixing hole. A locking portion is located on a second end of the locating member corresponds to the first fixing slot and the second fixing slot. The data storage device is fixed on a first position and a second position of the bracket.