In order to explore the feasibility of using biogas residue from the pig manure anaerobic fermentation biogas project as seedling substrate，it′s effect on maize，cucumber and rice was investigated.Residue was mixed with peat and vermiculite in a certain volume ratio to prepare the seedling substrate formulation.The plug tray nursery experiment was conducted to study the effects of pig biogas residue on the growth of crop seedlings，and an optimized range of biogas residues for each crop seedling substrate was obtained through comprehensive evaluation.Using the traditional seedling substrate formula(Peat∶Vermiculite = 60∶40)as the control treatment.Four treatments were set up:BR15(Peat∶Vermiculite∶ Biogas residue = 45∶40∶15)，BR30(Peat∶Vermiculite :Biogas residue = 30∶40∶30)，BR45(Peat∶Vermiculite:Biogas residue = 15∶40∶45)and BR60(Peat∶Vermiculite :Biogas residue = 0∶40∶60).The results showed that，compared with traditional seedling substrates，the addition of biogas residue improved the physical and chemical properties of the seedling substrate，such as bulk density，pH，available nitrogen，phosphorus and potassium content.The application of biogas residue in an appropriate proportion(15% and 30% for maize and cucumber，15% for rice)significantly promoted the growth of crop seedlings and biomass accumulation，and it was also beneficial to increase the relative germination rate，seedling index and vitality index of crops，but excessive application of biogas residue had negative effects.According to the regression analysis，the suitable application proportion of biogas residue for maize，cucumber and rice were 22.3%～32.4%，20.0%～24.0% and 10.2%～19.2%，respectively.In conclusion，the biogas residue from the pig manure anaerobic fermentation biogas project can be used as raw material for seedling raising，but the appropriate application ratio should be studied for different crops.