Abstract: Abstract: The technology of raising duck in paddy filed has good economic and ecological benefits for rice based agriculture. The past studies are usually only based on interaction effect between ducks and paddy. In this paper, we took the development of automatic duck feeding equipment that could adapt environment of paddy as its study object. Equipment for both automatic feeding system and automatic door system are crucial issues needed to be solved by adequate design, calculation and testing. Through the relevant experiment for the speed of ducks returning to cages, we gained optimal speed of the automatic door was 5r/min. The automatic door of the related calculation showed that the adaptive quality of the automatic door was 4.15 kg, moment of inertia was 0.24 kg·m2. The time of accelerating speed of automatic doors from 0 to 5 r/min was 0.0067s. According to the dynamic theory, we obtained the minimum torque of automatic door was 9.8 N·m. Automatic door powered by 15W DC gear motor. The DC gear motor can produce 28.6 N·m torque, which can meet the designed door requirement. Due to the hopper placed in the paddy field, feed was from more easily formed arch by affecting with damp, which influenced the control precision of feed quantity. So hopper with break-arch by vibration needed to be designed. For different kinds of feed angle of repose, the hopper's cone angle was designed to 60°. Taking advantage of the relationship between the DC motor armature current and DC motor torque, we measured the range of variation of torque during hopper discharging operation. The result showed that the minimum change rate of hopper torque appeared in transitional position between the body and the cone part, and the maximal load torque of the hopper was 47.79 N in the process of running. Based on the result of load torque, 24 V, 160 W 7.5 r/min DC gear motor was selected in the actuality. The optimal parameters of the break-arch that were measured by using of three factors at three levels orthogonal test were vibration eccentricity for 30 mm, rotating speed of 1200 r/min, vibration source location as below. Using the ternary quadratic orthogonal regression experiment of field experiment, we conducted researches on the optimal parameter between audio and automatic control system for maximizing the return rate of ducks. According to absolute value of coefficient in the regression equation, the factors affecting the rate of ducks return to cages were delay time of automatic door, sonic loudness and interaction between delay time of automatic door and sonic loudness in rank from big to small. At the same time, the maximum rate of ducks return to the cage was 98% from the equation in theory. Field experiment results showed that the closed delay time of automatic door was 1 min and sonic loudness was 100 dB, which would make the return rate of ducks achieve more than 97.5%. Under the same feeding condition, contrast experiment between manual feeding and automatic feeding was carried out. The test results showed that average weight of ducks in every week was not significant difference (P>0.05), which meant the designed automatic equipment could achieve the same result compared with manual feeding. The results were of great significance for improving automation level of rice-duck technology, accelerating the promotion and application of rice-duck technology.