Abstract: To screen light and cheap roof agricultural substrates, peanut shells, mushroom residues, cow dung, earthworm dung and other agricultural wastes were used as raw materials, the physicochemical properties of the seven substrates with different mixing proportions and their effects on the growth and quality of lettuce were studied by roof cultivation experiment. The grey correlation analysis was used to analyze the effects of various substrates. The results showed that the bulk density of mixed substrates was between 0.38 and 0.6 g/cm3, the total porosity of mixed substrates was from 54.77% to 74.17%, and the EC value ranged from 242 to 1150 μS/cm. Peanut shell and mushroom residue could significantly reduce the bulk density and increase the total porosity of substrates, while cow dung and peat had the most significant effect on nutrient content of substrate. Compared with CK, different substrates could promote lettuce growth, the plant height, leaf length, dry and fresh weight of T4[V(peanut shell): V(wormcast): V(vermiculite): V(perlite)= 3:4:2:1] and T5 [V(peanut shell): V(cow dung): V (vermiculite): V(perlite): V(peat) = 2:2:2:2:2] increased significantly. The soluble sugar and soluble solids content in lettuce increased significantly in T5. In general, T5, which has the best treatment effect and is suitable for lettuce cultivation, could be used as an excellent light substrate formula in roof agriculture.