Strip off-center is one of the major problems in hot strip mill line. The key to good centering is having good equipment, modern control systems, excellent maintenance and an understanding of milling process. Therefore, this study aims to develop a system that is useful for quantitative analysis of strip off-center. In this study, the measuring method of strip off-center was thoroughly studied and the exclusive control board to line scan camera were designed. Also, the manipulated type housing for line scan camera was developed to adjust initial parameters for strip width and center line. In order to check the accuracy and usefulness of the developed system, FM stand in $#2$ Hot Strip Factory in Pohang Steel Works was targeted.