A depressive state is a key risk factor for medical errors made by emergency life-saving technicians (ELSTs). However, no study has examined the occurrence of near-misses in ELSTs. We investigated the association between a depressive state and near-misses among ELSTs.A cross-sectional study was undertaken in 345 ELSTs using an anonymous self-administered questionnaire. The main exposure was a depressive state that was measured using the Quick Inventory of Depressive Symptomatology. For the main outcome, near-miss events, we calculated odds ratios (OR) of depressive states, adjusted for age and work-related factors by multivariable logistic regression. For exploratory purposes, we also undertook secondary analyses to determine whether work-related factors were associated with a depressive state.We obtained 254 responses. Compared to ELSTs without a depressive state, the adjusted OR for near-misses among ELSTs with a mild depressive state was 3.14 (95% confidence interval [CI], 1.37-7.16;  = 0.007), and that among ELSTs with a moderate or greater depressive state was 5.29 (95% CI, 1.46-19.09;  = 0.011). For a depressive state, in the exploratory analyses, the OR of nap duration while on duty for less than 2 h was 3.34 (95% CI, 1.15-9.67;  = 0.027), that for irregular mealtime while on duty was 3.71 (95% CI, 2.00-6.86;  < 0.001), and that for a duration of desk work of 4 h or longer was 2.21 (95% CI, 1.15-4.25;  = 0.017).A depressive state was significantly associated with the occurrence of near-misses among ELSTs. That a depressive state among ELSTs was related to nap duration and excessive office work indicates that improved management of the work environment and operations of ELSTs is necessary for the provision of safe emergency medical services.