The invention discloses a tunnel arch frame prefabricated construction device and method. The tunnel arch frame prefabricated construction device comprises a track arranged longitudinally along a tunnel and a trolley, wherein a pulley matched with the track is installed at the bottom of the trolley; the trolley is provided with a jacking device, and the jacking device includes a base for installing on the trolley; a jacking oil cylinder is fixedly arranged on the base, and the top of a piston rod of the jacking oil cylinder is connected with a supporting steel plate. According to the tunnel arch frame prefabricated construction device and method, the tunnel arch frame prefabricated construction device can cooperate with the installation of various arch frames with different cross-section shapes, and can adjust the jacking device of the trolley of the arch frame installation according to the sizes of the cross sections of the arch frames; the precise positioning of the arch frames can be realized, and the difficult problem of mechanized arch frame installation can be solved conveniently and quickly; and mechanized construction can be realized, the manual labor is reduced, the construction period is shortened, the construction speed is fast, fewer workers are needed on site, and a lot of costs are saved.