This study examined the effects of the nursing work environment, need satisfaction, and depression on turnover intention in South Korean nurses through a mediating model. This study was a descriptive cross-sectional research study and was conducted through an online questionnaire. A total of 248 nurses were recruited for this study. Data were collected in August 2022. Participants were invited to complete self-reported questionnaires that measure nursing work environment, need satisfaction, depression, turnover intention, and demographic information. The data obtained were analyzed using the dual mediation model applying the PROCESS macro (Model 6). This study analyzed the direct effects of the nursing work environment on need satisfaction, depression, and turnover intention. The nursing work environment also had indirect effects on their turnover intention via need satisfaction and depression. The mediating effect of need satisfaction, which affects the turnover intention by increasing the satisfaction of the nursing work environment, was found to be the greatest. It has been shown that the more positive a nurse’s experience of the nursing work environment, the higher the nurse’s need satisfaction. According to the study results, the increase in nurses’ need satisfaction greatly contributes to the decrease in depression and turnover intention. Therefore, active efforts should be made to improve the nursing work environment to fulfill basic needs.