A mounting apparatus for mounting a data storage device that defines a fixing hole therein includes a mounting bracket, a locking member, and an operating member. The mounting bracket includes a sideboard, and a first sidewall. The sideboard defines a through hole therein. The locking member arranged between the sideboard and the first sidewall includes a locking pin protruding therefrom. The locking pin is inserted through the through hole of the mounting bracket and configured for engaging in the fixing hole of the data storage device. A top of the locking member is pivotably connected to the mounting bracket. The operating member is arranged between the locking member and the first sidewall, and includes a resilient portion for pressing the locking member inward, and a first clip portion for clipping a bottom of the locking member for drawing the locking member to pivot outward. A top of the operating member is pivotably connected to the mounting bracket.