The trade-off between military expenditure and public health spending has remained an unsettled empirical issue. This paper investigates whether military expenditure has crowded out public health spending in 116 countries (including a subsample of 87 non-OECD countries) over the period 2000–2017. Through our system generalized methods of moments (GMM) estimations, we find that military expenditure, whether it is measured on a per-capita basis or as a proportion of total government expenditure, has a positive impact on the demand for health care. Nonetheless, we find a significant crowding-out effect of military expenditure on domestic government health spending by taking into account government fiscal capacity. The evidence we present supports the long-standing view that military expenditure has a particular ability to compete government financial resources away from publicly funded health spending. By interacting the military expenditure variable with income per capita, we find that an increase in income per capita has neutralized the crowding-out effect of military expenditure on domestic government health spending – less well-off countries stand to suffer most, and wealthy ones stand to suffer least, from the crowding-out effect. The crowding-out effect is statistically more specific to middle- and low-income countries in our samples.