In this paper, an on-line computing method is proposed for industry processes. Systematic on-line computing rules are developed for getting parameters of proportional plus integration and lead compensators. The performance of the compensated systems can be evaluated by specified phase margins and gain margins. The parameters of the found compensator can be re-computing if they are necessary. Four numerical examples give the proposed method provides better performance and robustness than those of other mentioned on-line computing methods. (C) 2009 Elsevier Ltd. All rights reserved.