Objective To investigate the mediating role of depressive symptoms between sleep and suicidal ideation among navy officers and soldiers. Methods The Pittsburgh sleep quality index (PSQI), self-rating depression scale (SDS) and self-rating idea of suicide scale (SIOSS) were used to survey 849 navy officers and soldiers by random sampling and group testing. The relationship among sleep, depressive symptoms and suicidal ideation, and the mediating effect of depressive symptoms between sleep and suicidal ideation were analyzed. Results A total of 849 questionnaires were sent out, and 812 valid questionnaires were collected, with an effective rate of 95.6%. Pearson correlation analysis showed that there were positive correlations between sleep quality, sleep latency, sleep disorder and depressive symptoms (r=0.446, 0.390, and 0.394, all P<0.01) as well as suicidal ideation (r=0.498, 0.462, and 0.420, all P<0.01); and depression symptoms were also associated with suicidal ideation (r=0.706, P<0.01). There were significant differences in the path coefficients of the model (P<0.05), and all fitting indexes were good (χ²=5.380, P=0.250). The mediating effect of depressive symptoms between sleep and suicidal ideation was 0.28, accounting for 41.2% (7/17) of the total effect. Conclusion Depressive symptoms play a partial mediating role between sleep and suicidal ideation among navy officers and soldiers.