The robotic technologies are leading a technological revolution in agriculture. Although wheeled chassis is commonly used in most general landform, it does not have a great ability to deal in rough terrains. In this research, an autonomous caterpillar equipped robot was developed for outdoor agricultural tasks especially in rough terrains. The robot system consisted of vision system, localizing system, and high-level and low-level controller. The A-star searching and dynamic window approach were used as global planner and local planner respectively, which could generate a collision-free path and send final velocity commands to robot. The navigation simulation and actual navigation experiments was conducted. As results, the mobile robot could cruise certain path accurately with RMSE of lateral offset around 5 cm during whole navigation process. The accuracy can satisfy the demands of most agricultural tasks.