Objective To investigate and analyze the psychological state of professional naval divers and to explore the influence of long-term diving on their psychological state. Methods A total of 170 professional naval divers (80 in shore-based environment and 90 in ship environment) and 155 non-divers in the same living environment (75 in shore-based environment and 80 in ship environment) were selected by cluster sampling. The general stress factor self-assessment (GSFS) scale, military job burnout scale, state-trait anxiety questionnaire, simple coping style questionnaire, and psychological resilience scale were used to investigate their psychological state. The psychological state was compared between divers and non-divers, between divers in ship environment and divers in shore-based environment, and between divers and non-divers in each environment. Results The GSFS score of divers was significantly lower than that of non-divers (P<0.01), the state anxiety score was significantly higher than that of nondivers (P<0.05), and the scores of 3 dimensions (hardiness, strength, and optimism) of psychological elasticity were significantly higher than those of non-divers (all P<0.001). The scores of GSFS, military job burnout, state anxiety, and trait anxiety of ship divers were significantly higher than those of shore-based divers (all P<0.05). In the ship environment, divers' positive coping score was significantly lower than that of non-divers (P<0.01), the scores of state anxiety and trait anxiety were significantly higher than those of non-divers (both P<0.001), and the scores of the 3 dimensions of psychological elasticity were significantly higher than those of non-divers (all PP<0.001). In the shorebased environment, the scores of GSFS, military job burnout and trait anxiety of divers were significantly lower than those of non-divers (all P<0.05), and the scores of the 3 dimensions of psychological elasticity were significantly higher than those of non-divers (all P<0.001). Conclusion The overall psychological state of professional naval divers is sound, but the psychological state of ship divers is worse than those of ship non-divers and shore-based divers. The long-term effect of dual stress factors of ship environment and diving may lead to the increase of trait anxiety of ship divers, which is worthy of attention.