In this paper, switchable Lane Keeping System (LKS) and Active Lane Keeping Assist System (ALKAS) with early/late intervention criteria is proposed and developed. These two systems are commonly based on single track vehicle model and weighted lateral deviation prediction. The main difference is intervention strategy between two systems. Software In the Loop (SIL), Man In the Loop (MIL) verification are fulfilled for both systems till vehicle speed 200kph. For real vehicle verification, only LKS results shall be shown in this paper which shows small maximum lateral deviation also in road transition and vehicle speed variation. Real vehicle verification results for ALKAS shall not be shown because it is more related to steering feeling of driver.