PURPOSE: To provide a discharge lamp lighting device, which sinks the higher harmonic component using a simple configuration..

CONSTITUTION: Power from commercial AC mains E is all-wave rectified by an all-wave rectifier circuit 2 to emit a ripple current, and a switching element Q4 is turned on and off with a good high frequency, and current is fed to the primary winding Tr2a of a transformer Tr2. The power induced in the secondary winding Tr2b of the transformer Tr2 is filtrated by a filter circuit 5 for emission of a DC output, and therewith a discharge lamp FL is lighted up by an inverter circuit 3. Because the output current of the secondary winding Tr2b is proportional to the output voltage of the all-wave rectifier circuit 2, it becomes a sine wave approximately, and higher harmonics are decreased. Also the rush current can be prevented because the portion corresponding to the inductance of the primary winding Tr2a is always connected with the switching element Q4. The two windings being insulated precludes occurrence of electric shock even at the time of discharge lamp FL replacement.