Abstract: A computer card reader adapting rack is disclosed for installing a card reader so that data can be read from and written to a memory card in the card reader. The computer card reader adapting rack comprises a support seat, a card reading circuit element, a fixing panel, and an upper cover. The support seat is a box having a size like a 3.5 inches floppy disk. A front side of the support seat is fixed with a panel having a memory slot. An upper side of the support seat is fixed with an upper cover. Moreover, the support seat are installed with respective auxiliary frames and the front side of the support seat has a connecting plate has a window for combining the panel, thereby, the computer card reader adapting rack is used at one of 5.25 disk slots and 3.5 inches disk slots.