This study was designed to clavify the decomposition characteristics of green fertilizer and soil nutrient changes of orchard after different mechanical methods to provide theoretical reference for efficient return and full utilization of orchard green fertilizer in a short term in southern Xinjiang. A field plot experiment was carried out on planting rape in soil between the rows of sweet pear orchard in southern Xinjiang. Four treatments were setup，including three mechanical returninggroups，i.e. shallow rotary tillerreturning(T1 -t1)，normalrotary tillagereturning(T2 -t2)，green fertilizer grinding rotary tillage integratedreturning(T3 -t3)and a blank controlgroup(CK). The decomposition and nutrient changes of rapeseed under different returning methods were investigated. The results showed that the decomposition characteristics and carbon and nitrogen release laws of rapeseed under the three returning treatments weresimilar，and the overall trend wasfast in the early stage and slow in the late stage. Compared with othertreatments，t3 treatment was more beneficial to thedecomposition and nutrient release ofrapeseed，and the first -order kinetic equation could be used to fit the relevant laws well. Soil pH value showed atrend of decreasing first and thenincreasing，and the other indexes showed a trend of increasing firstand then decreasing. Compared with 0d，the increase and decrease of each index were in the order of available potassium > alkali-hydrolyzed nitrogen > available phosphorus > organic matter >pH value. There were significant differences between soilindexes underT1，T2 and T3 treatments andCK( P<0.05). Amongthem，the increase and decrease range of soil indexes under T3 treatment wasobvious，and there was a certain correlation among soil indexes under the three mechanical returning treatments during the whole experiment period. The results indicated that the decomposition of rapeseed and its effects on soil nutrients under the T3-t3 returning mode were more significant than those of the other two groups in the short term. The results could be used as the main mechanical return mode of green fertilizer in orchards in southern Xinjiang.