Building steel structure welding seam detection device

The utility model relates to the field of welding seam detection, and discloses a building steel structure welding seam detection device which comprises a steel structure welding seam detector, bandages are fixedly arranged on the two side faces of the steel structure welding seam detector, a son hook-and-loop fastener is sewn on the front side of one bandage, a mother hook-and-loop fastener is sewn on the rear side of the other bandage, and the mother hook-and-loop fastener is sewn on the back side of the mother hook-and-loop fastener. A welding seam detection head is arranged below the steel structure welding seam detector, and a wire is connected between the steel structure welding seam detector and the welding seam detection head; the detection marking assembly is arranged on the weld joint detection head, the detection marking assembly comprises a connecting rod, a handheld rod, a micro pump body, a discharging pipe, a spraying head and a control button, the bottom end of the connecting rod is fixedly co