Abstract: Research on application of yellow sand in tomato grow seedling in gobi greenhouse can provide reference for tomato plug seedling in Kashi, Xinjiang Uygur Autonomous Region．'Fenbao' tomato was used as test material, plug seedlings used yellow sand at volume ratios of 0, 0.5, 1.0, 1.5, 2.0, 2.5 to replace perlite, and coconut bran ratios of 0, 1.5, 3.0, 4.5, 6.0, 7.5 to replace peat．Effects on seedling growth and physiological characteristics were investigated．Results showed that seedlings grown under T₂ treatment（peat∶ perlite∶sand = 7.5∶1.5∶1.0）exhibited better performance than other treatments, and yield the best comprehensive analysis results under membership functions, which could be used as the optimal sand ratio for tomato grow seedling in gobi greenhouse．Seedlings grown under Y₂ treatment（peat∶coconut bran∶perlite∶yellow sand = 4.5∶3.0∶1.5∶1.0）showed better performance than other treatments, and yielded the best results in comprehensive analysis of membership functions, which could be used as the optimal composite matrix ratio for tomato grow seedlings in gobi greenhouse．