Background: National freeway No. 5 which connected Taipei city and Yilan County had started transport in 2006. National freeway No. 6 which connected Taichung city and Nantou County had started transport in 2009. These roads would affect the local area. Purpose: Compare the difference of emergency medical service before and after the National freeway transport. Results: Obvious changes were noted at high emergency medical service demand areas and tourism areas. Conclusion: The government should note the effect and prepare early to face the change.