Zeno behavior in behavior-based system, which is two or more deterministic behaviors make infinite number of discrete transitions in finite time, can cause the motion speed and rotational velocity of the mobile robot change precipitately. Furthermore, the sharp shift of different behaviors will even exacerbate the absolute position errors. This paper present a new collision avoidance algorithm based on hybrid zeno behavior automaton which can eliminate the negative effect of the sharp shift of different behaviors. The core theoretical foundations on designing of the compound zeno behavior in hierarchical hybrid behaviors are presented, including the definitions of different type of behaviors and some theorems, which prove the feasibility of the algorithm. After that, the paper focuses on producing emergency behaviors that lead the mobile robot navigation around the obstacles without sharp shift of different behaviors. Simulation results illustrate the good performance of the control algorithms.