HighlightsThis study designed an air-suction jujube picking and conveying device to address the problems of low transport efficiency and high damage rate.Theoretical analysis, Fluent software simulation, and prototype testing determined the diameter of the conveying pipe, the inlet and outlet diameters of the suction chamber, and the fan type and speed.A Box-Behnken center combination design in Design-Expert software was used to perform response surface orthogonal tests to optimize the device.This study provides a reference for further optimization of the air-suction jujube picking and conveying device.Abstract. To address the problems of low transport efficiency and high damage rate, an air-suction jujube picking and conveying device was designed. The main components of the device include the fan, suction chamber, and conveying pipe. Simulation of the conveying pipe and suction chamber was performed using Fluent software, and the airflow rate and pressure were analyzed for conveying pipes of five different diameters and suction chambers with different inlet and outlet diameters. In the simulation results, the diameter of the conveying pipe was 105 to 165 mm, and the outlet diameter of the suction chamber was 150 to 210 mm. The Box-Behnken center combination design method in Design-Expert software was used to perform response surface orthogonal tests with the conveying pipe diameter, suction chamber outlet diameter, and fan speed as the test factors, and the jujube conveying rate and breakage rate as the target values. The results show that the order of the test factors on the jujube conveying rate is: fan speed = conveying pipe diameter > suction chamber outlet diameter, and the order of the test factors on the jujube breakage rate is: fan speed > suction chamber outlet diameter > conveying pipe diameter. The experimental results were verified in field tests with the optimized parameters. When the conveying pipe diameter was 165 mm, the suction chamber outlet diameter was 200 mm, and the fan speed was 3254 rpm, the average jujube conveying rate in the verification test was 238.68 kg h-1. The relative error between the experimental verification value and the theoretical optimized value was 1.44%, which is less than 5%. The average value of the jujube breakage rate in the verification test was 2.18%. The relative error between the experimental verification value and the theoretical optimized value was 3.81%, which is also less than 5%. This study provides a reference for subsequent research and optimization of the air-suction jujube picking and conveying device. Keywords: Air suction, Conveying device, Conveying pipe, Jujube, Suction chamber.