A mounting apparatus is configured for securing an expansion card with a support portion, and includes a chassis with a plate, and a securing member pivotably secured on the plate. The plate defines an opening for the support portion of the expansion card inserting therethrough. A positioning portion is formed on the plate to locate the support portion of the expansion card. The positioning portion defines a locking hole therein. The securing member includes a bent portion and a locking portion to sandwich the support portion of the expansion card and the positioning portion of the plate therebetween. A locking block protrudes from the locking portion to engage in the locking hole of the positioning portion. The locking portion is resiliently deformable to disengage the locking block from the locking hole of the positioning portion.