Abstract: The self-adaptive control was investigated in case that a weld line of tandem cold rolled strip work-piece is passing through a roll gap under conditions that there is no disturbance to the AGC system. The adaptive adjusting models were therefore developed for each and every roll gap on different mill stands. The application results of these models showed that the stability and control accuracy are both improved in the unsteady rolling state with the thickness fluctuation of strip head decreased at the exit of all stands, thus shortening the over tolerance length of products and raising the rate of finished products.