Purpose: The purpose of this study was to investigate influencing factors in self-efficacy among college students. Methods: The sample consisted of 553 college students in C & K cities. Self-report questionnaires were used to measure the variables. In data analysis, SPSS WIN 20.0 program was utilized for descriptive statistics, Pearson"s correlation coefficients, and regression analysis. Results: The mean score for Self-Efficacy was 66.62. Self-Efficacy was significantly different according to gender(t=2.076, p=.038), grade(F=11.077, p<.001), religion(F=4.666, p=.003), major(F=19.598, p<.001), economic status(F=6.570, p<.001), perceived health status(F=6.168, p<.001), and self-rated knowledge about health(F=12.936, p<.001). Multivariate analysis showed that major, self-rated knowledge about health, economic status, and perceived health status were significant predictors of self-efficacy and could explain 15.9% of total variability in this model. Conclusion: This study suggests that perceived health status and self-rated knowledge about health are significant factors in self-efficacy among college students. Therefore, the strategies of nursing intervention which improve these variables must be developed for college students.