PURPOSE: To provide a discharge lamp lighting circuit which can effectively avoid damage of a changeover switch caused by a high voltage pulse at lighting time of two arc tube installing type discharge lamp containing an arc tube having a high voltage pulse generating type starter.

CONSTITUTION: A changeover switch 26 is connected and arranged in series in a winding midway position, that is, between a front stage choke coil part 22a and a rear stage coil part 22b of a coke coil connected to a common line to the electric power supply side of an ordinary arc tube 12 and an arc tube 14 having a high voltage pulse generating system starter which are connected in parallel to each other. Thereby, direct impression of a high voltage pulse on the changeover switch 26 (impression through the rear stage choke coil part 22b) can be avoided, and since the damage can be prevented, contact point pressure of a contact point of the changeover switch can be reduced, so that the service life of the changeover switch can be lengthened.