The invention discloses fuel cell stack turnover equipment and a working method thereof. The turnover equipment includes a portal frame and a supporting pedestal; the portal frame vertically installedon the position of the two sides on the upper surface of the supporting pedestal; a lifting arm is installed on the vertical side of the portal frame through slide rails; the slide rails are respectively installed on the two sides of supports of the portal frame; the lifting arm is horizontally installed on the portal frame; the other side that the lifting arm is installed on the portal frame isspaced with the first support and the second support; and the first support is movably installed on the lifting arm through a movable disc. Through the turnover equipment installed in the middle position of an electric pile assembly line, an electric pile box can be smoothly clamped and finishes a turnover motion of 180 degrees, so that low efficiency of manual turnover can be avoided, and the speed of turnover can be accelerated; and the external structure of an electric pile box body can be accurately aligned with a pallet, so that demands of industrial mass production can be realized.