Bifidobacterium longum subsp. longum JCM 1217 (= ATCC 15707; = DSM32940) is an important probiotic that is involved in human milk oligosaccharide metabolism, gut homeostasis and immune regulation. Despite its biological significance, no whole cell kinetic model has previously been developed for this strain. This study developed the first ab initio kinetic model for B. longum JCM 1217 using annotated genome and biochemical reaction information was obtained from National Center for Biotechnology Information (NCBI) and Kyoto Encyclopedia of Genes and Genomes (KEGG) respectively. The metabolic network was reconstructed using the AdvanceSyn Toolkit, wherein the model represented a system of ordinary differential equations (ODEs) which incorporated Michaelis-Menten kinetics together with transcription and translation rate laws. The final model consists of 753 enzymatic reactions, 327 enzymes and 731 metabolites and was successfully simulated, showing model validity and potential prediction of dynamic intracellular metabolism.