Abstract Recently, Steel Industry has faced serious demands of products quality improvement and drastic competition of cost reduction in production. Hot strip finisher mill, in particular, is the important process in steel industry, and has to satisfy product quality and reduction of production cost as the user's demand. Now as for the products quality, thickness accuracy at head end and tail end remains open area to be improved by advanced control methods. And the operation support system at strip threading of strip is necessary to reduce the production cost. So this paper shows that AC drive system performance is successfully combined to decentralized method and that strip tension control has realized quicker response, and thai as the results, thickness accuracy has been improved drastically.