The　technology　of　active　sound　generation　(ASG)　for　automobiles　is　one　of　the　most　effective　methods　to　flexibly　achieve　the　sound　design　that　meets　the　expectations　of　different　user　groups,　and　the　active　sound　synthesis　algorithms　are　crucial　for　the　implementation　of　ASG.　In　this　paper,　the　Kaiser　window　function-based　the　harmonic　synthesis　algorithm　of　automobile　sound　is　proposed　to　achieve　the　extraction　of　the　order　sounds　of　target　automobile.　And,　the　suitable　fitting　functions　are　utilized　to　construct　the　mathematical　model　between　the　engine　speed　information　and　the　amplitude　of　the　different　order　sound.　Then,　a　random　phase　correction　algorithm　is　proposed　to　ensure　the　coherence　of　the　synthesized　sounds.　Finally,　the　analysis　of　simulation　results　verifies　that　the　established　method　of　the　extraction　and　synthesis　of　order　sound　can　meet　the　requirements　of　target　sound　quality.　　©　NVC　2023