This study aimed to investigate the impact of clan culture on nurses’ green behavior, with a specific emphasis on how paternalistic leadership operates as a mediator and workplace loneliness as a moderator. Descriptive correlational research was designed with 780 nurses from the Zagazig University Hospitals in Zagazig City, Egypt, who were chosen by systematic random sampling. Four instruments were employed to collect the data: The paternalistic leadership scale, the employee green behaviors descriptive norms scale, the clan culture scale, and the revised UCLA loneliness scale. There was a significant and positive correlation between clan culture and paternalistic leadership (r = 0.399, p < 0.01). Conversely, clan culture correlates negatively with green behavior (r = − 0.378, p < 0.01) and workplace loneliness (r = − 0.267, p < 0.01). Paternalistic leadership demonstrated a significant positive association with nurses’ green behavior (r = 0.386, p < 0.01) and a negative significant association with loneliness (r = −0.394, p < 0.01). The study concluded that clan culture has a strong and significant negative direct effect on green behaviors among nurses. While paternalistic leadership positively affects green behaviors. In addition, by fostering supportive leadership and integrating sustainability into cultural values, organizations can address both relational and ecological goals.