The invention relates to a steel sheet automatic binding machine which is characterized by comprising a rack, wherein the rack is fixedly provided with a first bracket, a second bracket and an adhesive tape hanging structure; a first end and a second end of a steel sheet are respectively and rotatably erected on the first bracket and the second bracket; and the free end of an adhesive tape on the adhesive tape hanging structure is connected to the steel sheet. Preferably, a first rotating wheel and a second rotating wheel are respectively and rotatably erected on the first bracket and the second bracket; the first end and the second end of the steel sheet are respectively inserted into the first rotating wheel and the second rotating wheel; and the first rotating wheel is in driving connection to a motor. When the binding machine disclosed by the invention works, the first rotating wheel is driven to rotate by the motor, the second rotating wheel and the steel sheet to be bound also simultaneously rotate accordingly and the adhesive tape on the adhesive tape hanging structure is drawn to complete binding on the steel sheet to be bound.