This paper presents the design of a high-power-density igniter with integrated LC resonator for low-wattage high-intensity discharge lamp ballasts. Electromagnetic integration technology is applied to reduce the number of passive components and the overall volume of the igniter. By applying the interwinding capacitance as the resonant capacitance, the integrated igniter is simply composed of a magnetic core and two magnet wire windings. By selecting the proper terminals and exploiting the advantage of an integrated LC resonant structure, the obtained output voltage is twice as much as an ordinary LC resonator. The design and implementation of the igniter are presented, while the experimental results of a small-signal measurement and a high-voltage test are given. The experiment results show that the application of passive integration technology into low-wattage passive modules is promising.