Xinjiang Uygur Autonomous Region is the major region for high quality dried processing jujube fruit. The period of jujube harvesting was usually after the frost to enhance the quality of jujube fruit. At this time, a large number of mature jujube fruit were fallen off from trees naturally. The method of jujube fruit harvester was usually picked-up from the ground. The jujube harvesting machine of air suction type was the most commonly used one among the jujube harvesters. Its working principle was to suck up the jujube fruit through negative pressure airflow. But when sucking jujube fruit, the impurities materials such as jujube leaf, jujube crane were sucking attached. Thus the cleaning device was employed to remove the impurities materials. Traditional cleaning devices would cause some problems such as high impurity, damage, and lost jujube fruit. Inertial airflow cleaning system was designed that utilized the difference between the mechanical properties and fluid properties of jujube fruit and impurity. The cleaning system was mainly composed of the feeding inlet, guide surface, closed-air aspirator, baffle, filtering impurities device etc. Then the structure size of the cleaning system was designed by combining the principle of cleaning and the principle of conservation of fluid flow rate. In addition, the guide surface shape was analyzed through characteristics of material motion trajectory and numerical analysis. Furthermore, Fluent software was used to simulate the flow field track in the clearing system. This can assess the flow field characteristics intuitively and determine whether swirling flow occurred that available for separating impurities with expectations. To analyze the influence regularity of single test factors on the evaluation index, the factors of airflow velocity and baffle opening size values were selected as the test factors. Meanwhile, the impurity rate, loss rate, and damage rate were chosen as evaluation indexes. The single factor tests were employed to determine the parameter interval. The results showed that airflow velocity and baffle opening size values were 32~38m/s and -1~4cm, respectively. Moreover, the central combination experimental method of Design-Expert 10.0.3 software was used to analyze the influence of the interaction factors on the evaluation index. After that, the analysis module were used to determine the optimal parameter values. The results showed that the impurity rate, loss rate, and damage rate were 1.32%, 3.25%, and 0.57%, respectively, when the airflow velocity was 32.0m/s and the baffles opening size was 3.4cm. Furthermore, the field tests were carried out at the combination of optimal parameters to verify the accuracy of the optimization parameters and the performance of the cleaning system. The verified results showed that the impurity rate, loss rate, and damage rate were 1.38%, 3.37%, 0.60%, respectively, which were increased by 0.06 percentage points, 0.12 percentage points and 0.03 percentage points respectively compared with the optimized parameters. The cleaning system can meet the requirements of jujube mixed cleaning operation and the research result can provide reference for the development of air suction type jujube harvester.