A discharge lamp operation apparatus includes an AC power supply (10), a voltage converting circuit (11), an inverter circuit (13), a load circuit (15), a controller (1), and a pulse voltage superimposing section (3). The pulse voltage superimposing section (3) controls the switching elements (Q3, Q4) of the inverter circuit (13) to superimpose a pulse voltage to the voltage applied across the discharge lamp (LA). The period until the discharge lamp (LA) is lighted is divided into a preheating period to preheat the discharge lamp and a startup period to start the discharge lamp. During the startup period, the controller (1) raises gradually the output voltage (Vdc) of the voltage converting circuit (11), and the voltage superimposing section (3) superimposes the pulse voltage on the voltage applied across the discharge lamp (LA).