Abstract: A prototype of a mobile harvesting robot has been designed and built for picking cucumbers in greenhouse in the Institute of Agricultural and Environmental Engineering in order to reduce labor fee for cucumber harvesting. The key technology of robot is software of image processing and its movement manipulating. Mobile robot of cucumber harvesting includes four parts: a vehicle, a manipulator, a vision system and an end-effector. The experiments show that the vehicle can move to the coarse position of working fast, the vision system can detect the precise position of mature fruit, and the end-effector can grasp the fruit and pick it up from the stem.