Abstract: An improvement method is proposed to solve a number of problems as staying with the conventional design of automatic alignment of the roller table，including so many hardware configuration，high costs of the spare parts and heavy workload of maintenance and adjustment as made during the operation and so on. The method involves such measures，including using Siemens cycle interrupt organization block，and replacing the original hardware such as the encoder，the high-speed counter module，and the encoder wheel, etc. with the software with the software to realize the automatic alignment function of the roller table. Relevant practice shows that the improvement as above mentioned is capable of meeting the on-the-site application requirements，simplifying the principle design and the hardware configuration so as to save the costs of the spare parts，reduce the fault points and workload for routine maintenance and adjustment. In general，the actual site application effectiveness is obvious.