A mounting apparatus for mounting a data storage device includes a bracket and a locking member. The bracket includes a first clamping arm and a second clamping arm pivotable relative to the first clamping arm. A number of mounting pins extend from each of the first and second clamping arms. The second clamping arm includes a first hook. The locking member is pivotably mounted to the first clamping arm and includes a second hook. When the second clamping arm is pivoted towards the first clamping arm, the first hook of the second clamping arm drives the locking member to rotate, until the second hook engages with the first hook and the mounting pins engage in opposite sidewalls of the data storage device.