This study aimed to identify the dietary behavior of experienced shiftwork nurses and the factors related to dietary behavior. Methods: This study was a secondary analysis based on the Shift Work Nurses' Health and Turnover study of Korean nurses. A total of 247 experienced shiftwork nurses were included in this study. The participants' dietary behavior, depression, level of occupational stress, fatigue, physical activity, and general characteristics were measured. Using SPSS 28.0, data were analyzed to obtain descriptive statistics and Pearson's correlation coefficients. Also, the independent t-test, one-way ANOVA, Kruskal-Wallis test, and multiple regression analysis were conducted. Results: Dietary behavior score of the participants using the Mini Dietary Assessment Index (MDA) was 29.35±5.67. 30% of the participants were depressed. Participants were experiencing moderate occupational stress. 74% of the participants did inadequate amount of physical activity. The influencing factors of shiftwork nurses' dietary behavior were having child(ren) (β=.16, p=.027), depression (β=-.13, p=.032), level of occupational stress related to occupational climate (β=-.13, p=.035), and inadequate amount of physical activity (β=-.17, p=.006). These factors explained 10.4% of the variance in experienced shiftwork nurses' dietary behavior scores. Conclusion:Experienced nurses with child(ren) tended to have healthier diets. However, when their level of occupational stress related to occupational climate was higher, when they were depressed, and when they did an inadequate amount of physical activity, experienced nurses were more at risk of having an unhealthy diet. Therefore, strategies are needed to encourage experienced nurses' physical activity and alleviate adverse occupational climate and depression.