The invention relates to the field of engineering, in particular to an automatic steel cutting and binding device. The steel cutting length and cutting speed can be changed by changing the rotating speed of a gear; steel pipes can be conveyed in batches; and intermittent cutting is achieved, a tape can be pulled out to bind steel, when a sliding block slides in a motor base, the rotating speed of a second rotating wheel is changed, then the transmission speed of a first belt is changed, rotation of a third rotating wheel is changed, the rotating speed of a first connecting rod is changed, the rotating speed of a first gear is changed, then the rotating speed of a second gear and the rotating speed of a third gear are changed, rotation of a first semi-rotating wheel and a second semi-rotating wheel is changed, the length of forward conveying of the steel is changed, and when the sliding block slides in the motor base, the rotating speed of a fifth gear, the rotating speed of two sixth gears and the speed of vertical reciprocating motion of straight teeth can be changed, and then the opening and closing speed of a cutting blade is changed, so that the length of a cut steel pipe is further changed.