Abstract: The tobacco suspending seedling experiment was carried on. The substrate is the Reyan No.4 king grass after the processing and fermenting and mixing with pearl rock and vermiculite with different ratio. the result shows there is significance difference between the two fermented grass meal under the different treatment and different ratio, and the several substrates of higher germination rates were picked out : when the diameter is 7, the treatment is 1 , the reaction degree is 80% and the ratio is 3:2:5, the two germination rates are 81.84% and 59.38% respectively; when the diameter is 4, the treatment is 2, the reaction degree is 100% and the ratio is 3:2:5, the two germination rates are 86.25% and 68.75% respectively.