The utility model discloses a peg roof beam, include: the roof beam body is the H -beam, the pterygoid lamina level sets up bottom surface under the last top surface of the roof beam body reaches, the perpendicular pterygoid lamina of web is vertical to be set up middle part position between the pterygoid lamina, the gusset includes first gusset, second gusset and third gusset, and it is all distinguished perpendicular web symmetry and sets up in the both sides of web, and the parallel and equidistant range of first gusset is at the web both ends, and the parallel and equidistant range of second gusset is at the middle part of web, and the third gusset is located between first gusset and the second gusset, and the third gusset is very little the same with first muscle board ruler, is equipped with the hole for hoist on the third gusset, two -layer and symmetrical setting was in the web both sides about the baffle divide into, and the perpendicular second gusset level of baffle sets up between the second gusset, the outside at the second gusset is connected to the shrouding. The utility model discloses can bear bigger load, have stronger bending resistance square ability and minimum amount of deflection deformation, greatly saved the cost, and peg roof beam life be longer.