The utility model discloses a safe profiled steel structure building, including truss and skylight, wherein, the truss comprises left truss and right truss, left side truss and right truss are by the main couple, the jack truss constitutes with the ring truss, the below of main couple is equipped with the bed -jig, the jack truss is equipped with between two main couples, and the one side that is located the jack truss between the main couple is equipped with the tie -beam, the outside of main couple is equipped with outside main couple, the other end of outside main couple is through ring truss connection, the main couple leans on subaerial one end fixed through burying the piece, main steel truss and middle jack truss in the middle of being equipped with between left side truss and the right truss, the skylight is located between the two middle main steel trusss, the utility model discloses in a safe profiled steel structure building, its simple structure, simple to operate, through setting up the skylight between left truss and right truss, the skylight about with the truss cooperate, can be better satisfy mechanics requirement, the security and the stability of effectual its use of assurance.