A mounting apparatus includes a mounting tray configured for securing an expansion card, a first securing member, a second securing member, a first rotating member and a second rotating member. The first securing member is attached to a first edge of the mounting tray, and a first stopper portion is disposed on the first securing member. The second securing member is attached to a second opposite edge of the mounting tray, and a second stopper portion is disposed on the second securing member. The first and second rotating members are rotatably secured to the mounting tray. A first and second hooks respectively extend from the first and second rotating members. The first hook is engaged with the first stopper portion, and the second hook engaged with the second stopper portion.