A mounting apparatus includes a chassis, a mounting member, a mounting tray and a securing member. The mounting member secures an expansion card and includes a flange. The mounting tray is received in the chassis and includes a top panel, a front panel and a retaining panel connected to the front panel. The securing tab extends from the top panel. The securing member includes a base engaged with the front panel and a securing plate substantially perpendicular to the base. The resilient arm extends from the securing plate along a direction substantially parallel to a surface of the base. A clasping portion is located on the resilient arm. The flange is located between the retaining panel and the securing member, the clasping portion is engaged with the securing tab, and the resilient arm is deformable in the direction to disengage the clasping portion from the securing tab.