The study aimed at explore effect of earthworm casts culture substrate on the improvement of cultivated soil and the growth of green plants in the air courtyard，reduce the exploitation of peat raw materials in commercial substrate and protect the ecological environment. In this study，the mixing of earthworm casts culture substrate and foundation pit soil was used to carry out pot experiment of Photinia fraseri Dress，and the effects of different culture substrate and soil ratio on soil physical and chemical properties，survival rate and growth of Photinia fraseri Dress were studied under simulated air courtyard environment. The results showed that the mixing substrates effectively increased soil organic matter，soil water content，total porosity and total microorganism，adjusted soil pH，reduced soil bulk density，and played a role in improving foundation pit soil. Among them，the 1∶3 ratio of earthworm casts culture substrate and foundation pit soil(T3)had the best effect on the improvement of foundation pit soil，and the survival rate and growth of Photinia fraseri Dress were better than that of the mixture of peat commercial substrate and foundation pit soil(CK2，T1 and T2)，and the survival rate of Photinia fraseri Dress was 76.19%. Compared with the optimal ratio of 1∶3 of peat commercial substrate and foundation pit soil(T1)，the survival of Photinia fraseri Dress was increased by 6.66%. Compared with CK1，the plant height，new shoot length，number of leaves and SPAD were increased by 24.7%，2.07 times，87.3% and 24.88%，respectively. Mainly，the 1∶3 ratio of earthworm casts culture substrate and foundation pit soil significantly increased the content of available phosphorus and available potassium in soil，which increased by 11.58 and 2.66 times compared with CK1，respectively. The total amount of bacteria，actinomyces and microorganisms significantly increased by 2.84，2.05 and 2.79 times compared with CK1，respectively. In particular，the number of phosphorus-solubilizing bacteria increased by 10.56 times compared with CK1，and 15.63% compared with CK2，which were conducive to the recycling of nutrients in soil，improving the survival rate of Photinia fraseri Dress and promoting its growth. Therefore，the earthworm casts culture substrate could replace the peat commercial substrate to improve the physical and chemical properties of the soil in the air courtyard，promote the growth of green plants，and reduce the development and utilization of peat resources.