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Background: Lactobacillus delbrueckii subsp.bulgaricus (Lb.bulgaricus) is an important species of Lactic Acid Bacteria (LAB) which is used in the cheese and yogurt fermentation.With many strains of this bacteria are genome sequenced, the reconstruction of genome-scale metabolic network models which have gained significant popularity as effective tools in metabolic engineering studies is available.Methods: The information of Lb.bulgaricus ATCC 11842-iZS225 is collected from KEGG, Uniprot, Entrezgene databases and the detailed information such as direction of reactions and isolated reactions are further revised carefully with large amount of bibliomic data.Flux balance analysis encoded in COBRA toolbox is used in the gene knockout and phenotype analysis.The fermentation experiment is executed to verify the simulation growth on minimum medium and different carbon sources.Results: We reconstruct a genome-scale metabolic network model of Lb.bulgaricus ATCC 11842-iZS225-which contains 225 genes, 516 reactions and 429 metabolites based on KEGG, Uniprot, Entrezgene databases and bibliomic information.The reconstructed model is used in the single gene knockout analysis and 87 essential genes for the growth of Lb.bulgaricus ATCC 11842 are obtained.The minimum medium specific for Lb.bulgaricus ATCC 11842 is then simulated and 23 components are included.The wet experiment further confirmed the growth of Lb.bulgaricus on its simulated minimum medium.Besides, its growth phenotype on eight carbon sources including galactose, mannose, fructose, ribose, xylose, sucrose, glucose and sorbose are calculated in the minimum medium and compared with the experiment.Conclusions: The genome-scale metabolic network model is a powerful tool for the understanding of the metabolic characteristics of an organism in depth.The genome-scale metabolic model of Lb.bulgaricus ATCC 11842 supplies a platform for the further study on its growth, metabolism and improving potential .