Introduction: Mental health is a serious concern among novice school nurses in Japan. Numerous novice school nurses with various health problems experience high stress levels, affecting their mental health. They may be experiencing reality shock, a known risk factor for burnout and turnover, or its factor, the "reality gap."

Objective: This study aimed to examine the hypothetical model by which the reality gap affects the mental health of novice school nurses.

Methods: This cross-sectional study conducted a self-administered questionnaire survey, and responses were obtained from 102 novice school nurses. A path model was created based on a hypothetical model.

Results: After several revisions on the hypothesis model, a modified path model was generated (CFI = .98, TLI = .93, RMSEA = .06). The path model showed that reality gaps negatively affected work engagement, work engagement positively affected intention to stay, and intention to stay positively affected mental health. Reality gap was also directly negatively associated with mental health. Having various support networks reduced the effects of reality gaps on mental health. Additionally, social support in the workplace boosted work engagement.

Conclusion: Unique from other studies, this study contributed to understanding the effects of reality gaps on mental health. School managers and administrators should establish a support system that enables school nurses to receive various supports from within and outside the school. In addition, novice school nurses should take advantage of networks and support inside and outside school to reduce reality gaps and grow as professionals.