In one embodiment, a lane assistant system is configured to provide lane assistance to a driver of an autonomous driving vehicle (ADV) based on the driver's intention determined at the point in time by capturing and analyzing user actions and driving environment surrounding the ADV. By analyzing the user actions and the driving environment surrounding the vehicle, the driver's intention can be determined. The driver's intention can be utilized to interpret whether the driver indeed intends to change lane. Based on the driver's intention, the lane assistance can be provided, either allowing the vehicle change or exit the current lane, or automatically providing warning or correction of the moving direction of the vehicle.