By applying the laser-linear array CCD detective technology, a high speed and high accuracy method for detecting roll wear is brought forward. The principle and composition of the detecting system has been expatiated. And a simulation-software program is compiled with Microsoft Visual Basic 6.0 based on this detecting principle. By using this simulation-software, the date of I/O signal for this system is gained. Also the signal verse is automatically drawn by this software. The experiment proves that the accuracy of the detecting system reaches to the demand of practical production process. This method offers the advantages of sensitivity, immediate response, no electromagnetic interference, simplicity and on-line non-contact detecting for roll wear.