Objectives: Although Asian immigrants have lower rates of smoking and binge drinking than other ethnics in the US, Korean Americans have the highest rate of Asian immigrants. This study, therefore, compared with the rates and examined the predictors of smoking and binge drinking by gender and ethnicity among Asian immigrants in California. Methods: In 2001 and 2003, California Health Interview Survey (CHIS) were conducted in English and their original languages with Asian immigrants residing in 58 Counties and 3 Cities, California. We performed analysis to find out the differences of smoking and binge drinking rates using the secondary data, CHIS 2001 and 2003. Multiple logistic regression analysis for survey data identified predictors of smoking and binge drinking behaviors by gender and ethnicity. Results: Korean American males (35.4%) and Japanese American females (15.4%) had higher rates of smoking prevalence compared with other Asian immigrants in California. In binge drinking, 26.5% of male and 8.1% of female among Korean Americans were binge drinker, and the rates were the top with Asian Americans who had lived in California. It showed the remarkable gap between gender of smoking and binge drinking among Vietnamese immigrants, whereas not the striking difference among Japanese Americans. In multiple regression models, age, educational level, occupation, marital status, English proficiency, and health insurance coverage remained significant for smoking and binge drinking behaviors(P<0.05). Even though the time in the US was not significant, it seemed to be related to educational level and English proficiency. In particular among female, smoking and binge drinking behaviors were associated with acculturation. Conclusion: Although Asian Americans had shared with American culture since they had immigrated in the US, they had significantly different prevalence rates of smoking and binge drinking based on gender and ethnicity. Therefore, future efforts should be focused on understanding differences by ethnicity and target at high-risk subgroups. To achieve this, it needs to develop the educational materials in Korean and their original languages.