Objectives: The purpose of this study is to analyze how the different lifestyles between Koreans and Korean Americans have significant effects on their health. Despite being the same race, Koreans and Korean Americans have different health conditions and health attitudes due to the acquired environmental factors such as social-economic factors, lifestyle risk factors, healthcare systems, and medical utilization. It is crucial to examine how the different lifestyle habits between Koreans and Korean Americans lead to various health conditions for establishing an effective health promotion policy. Methods: In this study, a comparative analysis was conducted using the National Health and Nutrition Survey of Korea and CHIS data of the United States in 2005 and 2015 to provide valuable insights when establishing such a policy. Results: The specific research purpose is as follows: First, socioeconomic factors, such as (1)living habits risk factors, (2)health satisfaction levels, (3)disease outbreaks, and (4)medical uses, are analyzed to find the distinct characteristics among Koreans, Korean Americans, and Americans. Second, the three groups --Koreans, Korean Americans, and Americans-- were compared based on their exposure to disease-related lifestyle risk factors related to their body mass index and their general health condition. The research results are as follows: First, all three groups improved health conditions in 2015 better than in 2005. Koreans maintained relatively higher general health conditions compared to other groups: their prevalence rate of chronic diseases such as diabetes, high blood pressure, heart disease, and asthma was lower than that of U.S. residents. Second, in regards to health behavior factors, the lifetime smoking experience for Koreans and Americans both decreased in 2015 compared to 2005, while the lifetime smoking experience for Korean Americans increased slightly. The number of smokers for Koreans has greatly decreased over a decade while that of Americans has moderately increased. Third, according to the results of the multiple regression, the general health conditions, which is a dependent variable, suggests that the number of men who answered they are healthy is greater than that of women in Korea, compared to the United States. Conclusions: In conclusion, the acquired environmental factors had more significant impacts on health than the racial factors did. Compared to 2005, the health behaviors and health levels of Korean Americans in 2015 gradually became more similar to those of Americans.