The present disclosure discloses a power-taking device for a rail guide vehicle. The rail guide vehicle includes a chassis travelling mechanism and a loading mechanism including a fixing plate, a power plate, an extension plate and a shifting fork, the fixing plate is fixed to the chassis travelling mechanism, the power plate and the extension plate can be translated, and the shifting fork is coupled to, can be translated in synchronization with, and can be rotated with respect to the extension plate. The power-taking device includes: a first conductive part, fixed to the fixing plate; a second conductive part, fixed to the power plate; and a third conductive part, fixed to the extension plate. When the first, second and third conductive parts are in contact, the power-taking device is turned on.