A discharge lamp lighting device includes: a power control circuit adapted to generate discharge lamp driving power; an alternating current conversion circuit adapted to execute polarity reversal on a direct current output from the power control circuit, thereby generating an alternating current; and a control section adapted to perform alternating current conversion control of controlling the polarity reversal timing of the alternating current, wherein the control section executes a steady drive process of executing the alternating current conversion control at a given frequency, a first low frequency drive process of executing the alternating current conversion control at a first low frequency driving frequency lower than the given frequency, and starting from a first polarity and ending with the first polarity, and a second low frequency drive process of executing the alternating current conversion control at a second low frequency driving frequency lower than the given frequency, and starting from a second polarity and ending with the second polarity.