Purpose: Korea is one of the most rapidly aging countries, accompanied by an increasing number of older adults with dementia. Certified-care-assistants are the primary care workers for these older adults. This cross-sectional descriptive study compared the factors influencing care behaviors among Korean and non-Korean certified- care-assistants in Korea. Methods: Participants, 113 Korean certified-care-assistants and 71 non-Korean certified-care-assistants, completed a survey questionnaire. The questionnaire was designed to assess dementia knowledge, attitude and care behaviors toward older adults with dementia. To determine the differences in these two groups, t-test was used. A stepwise multiple regression was performed to identify factors related to care behavior. Results: Significant differences in dementia knowledge, attitude and care behavior toward older adults with dementia emerged between Korean and non-Korean certified-care-assistants. Factors influencing care behavior varied by group. Dementia knowledge and education level were the significant factors of care behaviors in Korean certified-care-assistants, whereas attitude toward older adults with dementia was the significant factor in non-Korean certified-care-assistants. Conclusion: Findings indicate that different factors influence the care behavior of two groups. These findings can be utilized to develop certified-care-assistants’ training curriculum that needs to be tailored by nationality to improve the quality of care for older adults with dementia.