Abstract: Local trajectory planning is a key technology for an autonomous land vehicle(ALV), and its qualities closely relate to the performance of an ALV. In this paper, we embed the problem of modeling tasks and reactive behaviors of autonomous agents into the discrete event system framework for local trajectory planning. This technique overcomes the defects of potential field methods(as well as early virtual force field methods), i.e., the loss of some valuable information of the distribution of obstacles caused by the fact that all information was compressed into a single resultant force. This method improved the reliability of local trajectory planning of an autonomous land vehicle.