Abstract: Abstract: Soil aggregate as the fundamental unit of soil structure, is a product of interactions between soil microbial communities and mineral-organic compositions. High and sustainable soil aggregate stability is an important characteristic for preserving soil productivity and restraining soil erosion and degradation. However, there are few literatures about how biochar amendments affect soil aggregate in fruit orchards in China. The objective of this study was to evaluate the effects of combined application of peanut shell biochar and nitrogen (N) fertilizer on the distribution and stability of soil mechanical and water-stable aggregates, and jujube yields based on a three-year consecutive field experiment on fluvo-aquic soils in the North China Plain. This study could elucidate the responses of soil and jujube to soil fertility quality under biochar and N fertilizer application, which can provide a scientific basis for improving soil structure and high-efficient fertilization in jujube plantations. This experiment included 13 treatments: CK (no fertilizer), 4 levels of biochar amendments (C0-C3: 0, 2.5, 5 and 10 t/hm2) and 3 levels of N fertilizer application (N1-N3: 300, 450 and 600 kg/hm2). All samples were separated into 5 aggregate-size classes (>5, 2-5, 1-2, 0.25-1 and >0.25 mm) by dry and wet sieving. The results showed that compared with the control, biochar and N fertilizer amendments had no significant influence on mean weight diameter (MWD), geometric mean diameter (GMD) and the proportions of >0.25 mm macro-aggregates under dry sieving, while the proportions of >0.25 mm water-stable macro-aggregates increased with the biochar, and the highest proportion of this size was observed in the C3N2 treatment with the increment of 20.7%. The values of MWD and GMD under wet sieving were significantly increased by 29.2% and 27.2%, respectively. In addition, the percentage of aggregate destruction was significantly decreased by 27.1%. The contents of oil organic carbon were higher in biochar-amended treatments than in the control, and significant differences were observed for the higher application rates. A significant positive correlation was observed among soil organic carbon content, MWD and GMD (P<0.05) according to the correlation analysis. One year after the application of biochar to the jujube orchard, soil fertility under biochar and N fertilizer amendments increased with the increase of keeping years, and the yields of jujube were also gradually improved. Taking into account the above-mentioned results, we can draw the conclusion that biochar amendment combined with N fertilizer application significantly improved the content of soil water-stable aggregates and aggregate stability, which was conducive to ameliorate soil degradation, and improve jujube yield. The optimal amounts for biochar and N fertilizer according to the comprehensive results should be 10 t/hm2 and 300 kg/hm2, respectively.