Objectives: The purpose of the study is to investigate the factors associated with gingival bleeding(GB) by tooth brushing in college students. Methods: A self-reported questionnaire was filled out by 232 college students in Daegu Health College from March to June, 2014. Data were analyzed for frequency, chi square test, and logistic regression analysis using SPSS 12.0 program. The study was a cross sectional study. The questionnaire consisted of general characteristics of the subjects(gender, age, marital status, and smoking), frequency and duration of tooth brushing, scaling experience, and physical health status. Self-reporting hemorrhage was reported by yes or no. Frequency of tooth brushing was documented as the number of behavior. Above 4 times of tooth brushing was defined as 4. Duration of tooth brushing was documented as minute. Above 4 minutes, it was recorded as 4. In physical health status, 1 is feeling weak and 4 is feeling very healthy. Cronbach alpha was 0.82 in the study. Results: There were significant relationships between gingival bleeding and age(p<0.05), subjective health(p<0.01), tooth brushing frequency(p<0.05) and duration(p<0.05) by chi square test. Logistic regression analysis showed that the age(p<0.05), subjective health(p<0.01), tooth brushing frequency(p<0.05) and duration(p<0.05) were associated with gingival bleeding. Prevalence of gingival bleeding in 20 years was 0.62(odds ratio 1.85, 95% CI 1.00~3.43) and it was higher than that in 10 years. Prevalence of gingival bleeding in good health group was -1.38 and it was lower than that in poor health group. Conclusions: The factors associated with gingival bleeding were age, subjective health, and tooth brushing frequency and time.