With the advent of the post-genomic era, metabolic engineering of microorganisms plays an increasingly important role in industrial production. The genome-scale metabolic model (GSMM) integrates all known metabolic information in the organism to provide an optimal platform for global understanding of the metabolic state of the organism and rational guidance for metabolic engineering. As a model strain, Lactococcus lactis NZ9000 plays an important role in industrial fermentation, but there is still no specific genome-scale metabolic model for it. Based on genomic function annotation and comparative genomics, we constructed the first genome-scale metabolic model iWK557 of L. lactis NZ9000, which contains 557 genes, 668 metabolites, and 840 reactions, and further verified at both qualitative and quantitative levels, to provide a good tool for rationally guiding metabolic engineering.