Objective To explore the mediating effect of positive psychological capital between nurses′ spare time planning and occupational stress, and to provide a reference for nursing managers to implement targeted human resource management strategies and reduce nurses′ occupational stress.Methods From May to July 2024, totally 827 clinical nurses from four tertiary hospitals in Gansu province were selected utilizing convenience sampling method.Then they were investigated by using the Leisure Crafting Scale, the Chinese Nurses Stressor Scale (CNSS), and the Positive Psychological Capital Questionnaire (PPQ).Results The scores of spare time planning, CNSS and PPQ were (26.84±7.80), (95.76±15.78) and (112.34±17.92) respectively.The score of spare time planning negatively correlated with CNSS score, and positively correlated with PPQ score (both P＜0.05), and there was a negative correlation between the score of CNSS and PPQ (P＜0.05).Positive psychological capital played a partial mediating role between nurses′ spare time planning and occupational stress, and the mediating effect accounted for 42.42% of the total effect.Conclusion Nurses′ occupational stress is at a medium level, and nurses′ spare time planning can indirectly affect their occupational stress through positive psychological capital.Nursing managers should pay attention to nurses′ positive psychological capital, help nurses set reasonable spare time planning goals to reduce their occupational stress.