Abstract: Emissions of biogas slurry have been increasing year by year, resulting in deleterious effects on soil properties in agroforestry ecosystems. Biogas slurry is not only rich in nutrients such as nitrogen, phosphorus, potassium, organic matter, humic acids and growth hormones, but also in heavy metals and antibiotic content. Biogas slurry can be reasonably used as a sustainable resource; however, it has the potential to cause soil and environmental contamination. The objective of this study was to provide scientific reference for the rational utilization of biogas slurry to improve soil and maintain soil productivity. We reviewed recent research on the effects of diogns slnmy on soil to understand the effects of biogas slurry application on soil properties in agroforestry ecosystems as followed: ① Appropriate application of biogas slurry increases the abundance of soil fauna, microorganisms, total N, total K, total P, available N, available P and available K. ② The effects of biogas slurry application on soil properties are influenced by the nature and structure of the soils, and by the dosages and application times of the slurry. ③ Biogas slurry application could increase the soil content of heavy metals, with the degree of increase varying at different soil layers. ④ Different biogas slurry raw materials and variation in fermentation times might lead to variable effects of biogas slurry on agroforestry soils, as could variation in soil adsorption capacity, accumulation of heavy metals, soil nutrient elements, and soil fauna abundance, stages of growth, and growth rates, in addition to other factors. Compared with raw biogas slurry, diluted biogas slurry irrigated in soil is more likely to cause accumulation of Cd and Cu, and the inhibition effect on soil fauna is more pronounced in fresh versus aged slurry.The application of biogas slurry is an important approach for sustainable recycling of resources. Rational application of biogas slurry can not only increase soil productivity,but also can protecting the environment. However, processes and mechanisms of biogas slurry’s effects vary with biological, physical, and chemical properties of different types of agroforestry soil. Therefore, we suggest that long-term observations of the responses of agricultural and forest soil to biogas slurry application should be conducted, including investigations on the physical and chemical properties of biogas slurry, and specific site conditions. Hence, this would also involve deeply exploring the migration processes and adsorption of biogas slurry in the soil. Thus, biogas slurry has the potential to gain considerable significance in the long-term maintenance of soil productivity in different agroforestry lands in the future.