An integrated stage for holding rapid test reagent cards includes two U-shaped sidewalls opposite to each other, a first receiving space, a second receiving space, and an elastic sheet. The U-shaped sidewalls cooperatively define the first receiving space. The second receiving space is formed in the first receiving space and is lower than the first receiving space. The elastic sheet is arranged on a short side of the first receiving space. The first receiving space is used for allowing the integrated stage to hold a first rapid test reagent card. The second receiving space is used for allowing the integrated stage to hold a second rapid test reagent card. The integrated stage utilizes the elastic sheet to hold and fix the first rapid test reagent card or the second rapid test reagent card.