The utility model discloses an outdoor optical splitter mounting rack with a lightning protection function. The device comprises a support frame and a fixed base, grooves are formed in the two sides of the upper surface of the fixed base; a first rotating shaft is rotationally arranged in the groove; the surface of the first rotating shaft is sleeved with a lantern ring; a bracket is arranged on one side of the surface of the lantern ring; a fixing ring is welded at the other end of the bracket; a clamping block is welded on the other side of the surface of the lantern ring; A clamping grooveis formed in the lower surface of the groove, the clamping block is rotationally clamped in the clamping groove, the four sets of supporting frames are arranged, first lightning rods are arranged at the tops of the four sets of supporting frames, annular grooves are formed in the outer surfaces of the four sets of supporting frames, and mounting plates are arranged among the four sets of supporting frames. According to the utility model, the first lightning rod is arranged at the top of the support frame, so that thunder and lightning can be guided into the ground through the connecting wire in the support frame, thereby achieving the lightning protection effect.