The utility model provides a steel construction burglary -resisting door for building, including relative first door plant, second door plant and the sight glass subassembly that sets up, be equippedwith first through -hole on the first door plant, be equipped with the second through -hole on the second door plant, first through -hole and second through -hole set up mutually by mistake, all sealon first through -hole and the second through -hole and are equipped with the anti -theft net, the sight glass subassembly includes that " Z " shape of compriseing stainless steel fixture is gone intothe optical channel and is located into the interior at least a set of reflector of optical channel, income optical channel one end and the optical channel other end and second through -hole intercommunication are gone into to first through -hole intercommunication, in the reflector is located and is used for in the optical channel reflecting the burglary -resisting door with the scene outside the burglary -resisting door. The utility model provides a pair of steel construction burglary -resisting door for building adopts the support to constitute the increase of " Z " shape income optical channel and goes into the optical channel tortuosity to and set up the anti -theft net on first through -hole and the second through -hole, thereby can prevent that thief's utensil from stretching intopushes down the handle family of a general in the burglary -resisting door and opens, the degree of safety of increase burglary -resisting door.