In order to reduce the picking technical difficulty and cost of fruit，a mechanical device used for picking high-branch fruits is designed and developed，which based on frequency control of vibration. Based on mechanical analysis and theoretic calculation，the design scheme of main transmission is determined by bevel gear and crank slider mechanism，and then fruits picking is realized through converting output torque of DC motor into reciprocating vibration of the branches. The vibration process of the branches is simulated by linear spring，and an equivalent mechanical model based on rigid-flexible coupling is designed and created. After that，the rationality and reliability of the prototype are verified by kinematics and dynamics simulation. Picking experiment of the physical prototype shows that，the device has good practicability and fruit picking efficiency. The results provide an important technical reference for innovative design and practical application of the fruits picking machinery.