Straw returning is an effective way to enhance the number and diversity of soil organisms, but the responses of soil arthropods to straw returning are still unclear. In this study, we conducted a meta-analysis involving 230 comparisons of soil arthropod number and 112 comparisons of soil arthropod diversity collected from 25 related literatures during 2005-2020. The objectives of this study are to assess the effects of straw returning on the number and diversity of soil arthropods in agroecosystems of China, as well as the variation of these effects under different climates, soil depths, cropping systems, straw returning amounts, straw returning methods and time. The results showed that straw returning significantly increased the number of soil arthropods compared with no straw returning, except the studies conducted at subtropical monsoon climate regions, or the time of straw returning was more than 5 a. In addition, the promotional effect of straw returning on soil arthropod number was also affected by the size of arthropods, with straw returning significantly increasing the number of small and medium-sized soil arthropods, especially acari, rather than large soil arthropods. Straw returning also had a tendency to increase the diversity of soil arthropods, and this effect was significant under the conditions of temperate monsoon climates, mean annual temperature less than 5℃, mean annual precipitation less than 600 mm, rotation cropping, amount of straw returning more than 10000 kg/hm² and straw returning time more than 5 a. The regression analysis showed that the increased rate of soil arthropod number under straw returning significantly decreased with straw returning time, but it significantly increased with straw returning amount; the increased rate of soil arthropod diversity under straw returning decreased significantly with mean annual precipitation, but it significantly increased with straw returning amount and time. Together, these results indicated that straw returning could improve the number and diversity of soil arthropods, which could be affected by climate factors and agricultural managements.