A lighting driver for a discharge lamp is provided. The discharge lamp is designed to be ignited in response to application of a voltage higher than a given set voltage and to maintain stable emission of light through supply of a given current. The lighting driver includes two voltage source circuits one of which applies a first voltage having a first frequency to a piezoelectric transformer for igniting the discharge lamp and the other applying a second voltage of a second frequency for keeping stable emission of light from the discharge lamp. The lighting driver also includes a frequency switch which switches between communication of the first voltage source circuit with the piezoelectric transformer and communication of the second voltage source circuit with the piezoelectric transformer depending on whether the discharge lamp has been ignited or not, thereby keeping the stable emission of light from the discharge lamp after ignited.