Today, there is a demand for research on the concept of career related to the changing environment due to severe environmental change. Career adaptability is a readiness for both predictable and unpredictable changes. In this study, based on Social Cognitive Career theory the researcher selected emotional intelligence as an individual variable and social support as an environmental variable, and analyzed the relationship of the influence on career adaptability by these variables and effect of career decision self-efficacy as a mediator. A multiple regression analysis was conducted on 507 data across from the 12 universities. The findings are aw follows: First, emotional intelligence had a statistically significant effect on career adaptability. Second, social support had a statistically significant effect on career adaptability. Third, career decision self-efficacy has a partial mediating effect on emotional intelligence and social support in relation to career adaptability. Among emotional intelligence and social support, emotional intelligence had more influence on career adaptability. Implications for research and practice are discussed.