A　dynamic　heat　transfer　model　based　on　the　lumped　parameter　method　was　developed　for　cooling　system　of　vehicle　internal　combustion　engine.　Engine　combustion　chamber　heat　transfer,　radiator　heat　transfer,　water　pump　heat　transfer　were　included　in　the　model.　The　heat　coupling　between　the　engine　block　and　coolant,　radiator　and　coolant,　water　pump　and　coolant　were　formulated.　An　example　simulation　was　implemented　for　a　single　cylinder　diesel　engine.　The　results　show　that　this　model　can　be　used　for　studying　heat　performance　of　cooling　system.