Diversified cropping system is an important strategy of ecological intensive agriculture. It makes significant improvements to soil quality, ecosystem stability and land productivity. Under the background of a global shortage of food supply and cultivated land, diversified cropping system play an increasingly important role in ensuring food security and improving the quality of cultivated land in China. Currently, diversified cropping system has become a research hotspot in soil, ecology, crop, and tillage sciences. Nevertheless, the research about diversified cropping system in the recent period is more focused on improving its biodiversity and ecological functions but with limited understanding of how these diversified systems impact soil quality and productivity due to the changes of soil physical, chemical, and biological properties. In this paper, we analyzed the connotation of diversified cropping system and its significance on promoting soil health and improving ecological service function, and systematically summarized the advances in the effect of diversified cropping system on some soil properties including: (1) Physical properties: We focused on the improvements of soil porosity, aggregates, water binding capacity, etc., by different crop root morphology (biological tillage) and straw inputs under diversified cropping system. (2) Chemical properties: We analyzed diversified cropping system optimized light, water, and heat resources to increase the utilization efficiencies of nitrogen and phosphorus, promote soil organic carbon sequestration, balance soil nutrients and regulate root exudates, mitigate using differences in spatial and temporal niche and nutrient niche between aboveground and underground parts. (3) Biological properties: We reviewed the biological effect and advantageous changes of soil biodiversity under diversified cropping system including soil microbial diversity, arbuscular mycorrhizal fungi, soil enzyme activity, and soil animals. However, there are still some challenges limiting the development of diversified cropping systems including the lack of theoretical systems, production technology and machinery equipment, technological polarization, and policy support. Furthermore, we proposed four areas where future research should focus on improving cultivated land quality by diversified cropping system: (a) Develop multi-functional diversified cropping system including soil amendment, bioremediation, and low-carbon cropping system; (b) Supplement the theoretical system of cultivated land quality improvement under diversified cropping system including crop-soil interaction mechanism and nutrient regulation, ecological versatility and environmental response mechanisms at different scales; (c) Establish appropriate technology system for diversified cropping system including suitable special varieties or their combinations, optimization production technology and machinery equipment; and (d) Applicability and popularization strategies of diversified cropping system including planning and design, policy guidance and financial support to establish typical diversified cropping system in different regions. On the whole, this review provides a reference for the diversified cropping system to play a greater role in the strategy of improving cultivated land quality.