As a fundamental soil component,soil microorganisms can sensitively,timeously,and accurately reflect the status of the change of soil quality and reveal the condition of soil fertility and improvement,which are important indicators of soil quality.At present,subsoiling technology is considered a soil conservation-tillage technology,which can change the soil structure and influence the soil microbial community.Therefore,the effect of tillage methods on microbes in soil ecosystems is being well studied globally.However,little is known about effect of subsoiling on soil nutrients and the functional diversity of microbial communities in rhizosphere soil of Glycyrrhiza uralensis.The purpose of this study was to provide the basis for improving tillage practices and soil environmental condition of licorice.Compared to conventional methods,Biolog technology can effectively provide useful information on soil microbial community functional diversity.Therefore,in this study,two treatments,including rotary tillage (CK) and subsoiling,were conducted in licorice planting land.Using field experiments and laboratory analysis,the effect of subsoiling on soil nutrients and the functional diversity of microbial communities in rhizosphere soil of G.uralensis was determined.The results showed that the effect of subsoiling on soil nutrients in the 0-20 cm depth of rhizosphere soil of G.uralensis was not significant,but greatly improved the total nitrogen (TN),phosphorus (TP),and potassium (TK) contents in the 20-40 cm depth of rhizosphere soil of G.uralensis(which increased by 60.8,65.3,48.9,and 86.8%,respectively).Meanwhile,the number and abundance of bacteria,fungi,and actinomycetes within the 0-20 and 20-40 cm depths of rhizosphere soil of G.uralensis was significantly increased (P < 0.05).The quantity of three types of microorganisms present in the upper layer was greater than in the lower layer,and was greater in the subsoiling than non-subsoiling.After 156 h of microbial incubation,Average Well Color Development (AWCD) of different soil layers of subsoiling treatments were obviously higher than those of non-subsoiling treatments,and subsoiling treatment significantly improved the utilization of AWCD (72 h,P < 0.05),by 35.5 and 130.8% in the upper and lower soil layers,respectively.Compared with the non-subsoiling treatment,subsoiling significantly increased the microbial diversity index (such as the Shannon Index (H),Substrate Richness Index (S),and Simpson's Dominance Index (D)).A principal component analysis (PCA) showed that subsoiling treatment could optimize microbial community composition in licorice rhizosphere soil;polymers,carboxylic acids,amino acids,and carbohydrates were primary carbon sources of rhizosphere soil microbes in subsoiling areas.Overall,the nutrient content of soil,the number of microbes,and the microbial community diversity index were obviously improved by subsoiling in licorice rhizosphere soil,and the microbial community functional diversity was changed.The arable layer soil structure was enhanced,and therefore the survival of microorganisms was improved by subsoiling.Therefore,subsoiling treatment could effectively improve the quality of rhizosphere soil of G.uralensis.