This paper reports empirical evidence on the impact of the prevalence of COVID-19 on voter turnout, using the data from the legislative elections in Korea. To control for the time-invariant constituency-specific factors, I regress the first-difference in turnout, i.e. the change from the previous election, on the cumulative number of COVID-19 cases per resident. The results show a substantially negative impact. The share of old-age voters, who are known to face worse health risks of COVID-19 infection, amplifies this impact. These findings raise the question whether it is more democratic to hold elections as scheduled, as opposed to postponing them, during a pandemic.