A discharge lamp lighting apparatus includes a power control circuit that outputs a DC current, an AC conversion circuit to which the DC current is inputted, the AC conversion circuit repeatedly reversing the polarity of the DC current between a first polarity and a second polarity at predetermined timings to produce and output a discharge lamp driving AC current, and a controller that controls the AC conversion circuit to perform AC conversion control in which the timings at which the polarity of the discharge lamp driving AC current is reversed are controlled and controls the power control circuit to perform section current control in which the magnitude of the DC current is controlled in each polarity reverse timing section. In the section current control, the magnitude of the DC current is controlled in accordance with a periodic pattern in each of the polarity reverse timing sections to control the ratio of accumulated energy supplied to each electrode of the discharge lamp in the first half of the polarity reverse timing section to that in the second half of the polarity reverse timing section.