From 2020 to 2021，with jujube monoculture(CK)and alfalfa monoculture(AM)as the control，three different spacing of red jujube intercropping alfalfa planting patterns were set up through field experiments:M1(0.5 m spacing)，M2(1 m spacing)and M3(1.45 m spacing)were used to study the variation characteristics of soil aggregate organic carbon，total nitrogen and yield of alfalfa intercropped with red jujubes at different spacings. The results showed that the soil mechanical stable aggregates were dominated by large aggregates，mainly concentrated in 0.25-1 mm grain size，with a range of 23.26%-28.01%. Compared with CK treatment，the contents of≥0.25 mm mechanical stable aggregates and water-stable aggregates in 0-60 cm soil layer of M1，M2 and M3 treatments increased by 12.84%，16.46%，13.75% and 42.57%，43.50%，32.13%，respectively. The intercropping treatments significantly increased the average mass diameter of mechanical stable aggregates and water-stable aggregates in 0-60 cm soil by 19.53%，23.58%，14.29% and 21.31%，21.50%，10.80%，respectively，compared with CK. The order of organic carbon and total nitrogen content under different planting patterns was M1 > M2 > AM > M3 > CK，M2 > M1 > AM > M3 > CK，respectively. The contents of organic carbon and total nitrogen in microaggregates of < 0.25 mm were the highest，and the contents of organic carbon and total nitrogen in aggregates of 1-2 mm were the lowest. M1 and M2 treatments significantly increased soil organic carbon and total nitrogen contents in 0-60 cm soil layer. The yield of fresh grass in AM treatment was the highest and significantly higher than those in other treatments. The yield of M2 was the highest and that of M3 was the lowest in all intercropping treatments. Intercropping alfalfa had no effect on the yield of red jujube. The intercropping alfalfa treatment with 1 m spacing of red jujube optimized the soil structure and nutrients，and ensured the balance of crop yield，which was the most suitable alfalfa spacing mode.