In order to comprehensively evaluate the effects of incorporating into soil the mixture of leguminous and non-leguminous green manure on the dry matter accumulation, the leaf photosynthetic characteristics, distribution rules and yield of double cropping rice, from April 2018 to November 2019, six treatments were designed with early rice variety Zhongzao 39 and late rice variety Yuzhenxiang as materials, including no green fertilizer(CK), milk vetch(T1), milk vetch and ryegrass(T2), milk vetch and oil rape(T3), arrow tongue pea and ryegrass(T4), arrow tongue pea and rape(T5). The results showed that compared with CK, returning green fertilizer to the field significantly reduced the net photosynthetic rate of leaves and population dry matter accumulation in the early growth stage of early rice, and significantly promoted the dry matter accumulation in the late growth stage of early and late rice, and increased the net photosynthetic rate of flag leaves. The average yield of two-year double cropping rice increased by 2.88%-14.74%. Compared with T1, T3 and T5 treatments were conducive to the formation of high light efficiency population in early and late rice, the dry matter accumulation in mature stage of early and late rice increased significantly, and the net photosynthetic rate of flag leaf maintained at a high level. The effective panicles, seed setting rate and yield of double cropping rice were significantly affected by the mixed return of leguminous and non-leguminous green fertilizers, and there was a significant positive correlation between the effective panicles, seed setting rate and yield of double cropping rice(P<0.05). Compared with CK, the yield of T3 treatment was the highest, which was 17.13 t/hm2, and the yield of two-year double cropping rice of T3 treatment increased by 14.74%. The mixed returning of milk vetch and rape could effectively improve the chlorophyll content of leaves in the later growth stage of double cropping rice, delay the decline of net photosynthetic rate of flag leaves, promote the dry matter accumulation and distribution of double cropping rice, and significantly improve the dry matter accumulation and rice yield at maturity, which indicate the mixed returning of milk vetch and rape is a more suitable green fertilizer mixed returning model.