[Object] To provide a lighting device which enables a user of an illumination fixture to select any of a fluorescent lamp and a DC lighting light source as represented by a light emitting diode, and further realizes safe use. [Means for Settlement] A lighting device has first control means 11 adapted to output a driving signal to switching elements Q1 and Q2 which are used to drive a discharge lamp La at high frequency via a resonance part 4, and second control means 12 adapted to output a driving signal to a switching element Q3 of a voltage conversion circuit (i.e. DC/DC conversion part 5) which steps down an output of a DC power source circuit 1, and the lighting device includes an inductor (i.e. preheating transformer T1) having secondary windings n2 and n3 for use in supplying a preheating current to a filament of the discharge lamp La, and a rectifier DB for rectifying a voltage in an output end of at least one of the secondary windings n2 and n3 (i.e. secondary winding n2), wherein an output path of the voltage conversion circuit (i.e. DC/DC conversion part 5) is connected in parallel with an output path of the rectifier DB.