A mounting apparatus includes a mounting bracket and a securing element. The mounting bracket is configured to mount an expansion card. The mounting bracket is mounted in a chassis. The securing element includes a positioning member mounted to the mounting bracket, a mounting member mounted in the positioning member, and an elastic member surrounding the mounting member. The positioning member includes a first stopping portion. The mounting member includes a contact portion and a threaded portion engaging the chassis. The elastic member is resiliently compressed between the first stopping portion and the contact portion. The elastic member is configured to bias the threaded portion away from the chassis.