An optical device includes a light modulation device disposed on an optical axis of incident light, and a holding section configured to hold the light modulation device. The holding section includes an inflow part to which a liquid supplied from an outside of the holding section inflows, a flow channel forming part disposed along a circumferential edge of the light modulation device so as to have an annular shape, and having a flow channel through which the liquid flowed from the inflow part circulates, and an outflow part from which the liquid having flowed through the flow channel outflows to the outside of the holding section. At least one of an inside of the inflow part and an inside of the flow channel is provided with at least one projection.