A lamp driving circuit includes: a first voltage generator which receives a direct current power voltage and outputs a first square wave voltage in response to a first switching signal and a second switching signal having a phase inverted with respect to the first switching signal; a second voltage generator which outputs a second square wave voltage in response to a third switching signal having a phase shifted by a predetermined time with respect to the phase of the first switching signal and a fourth switching signal having a phase inverted with respect to the phase of the third switching signal; and a transformer which receives the first square wave voltage and the second square wave voltage and boosts a first driving voltage defined by an electric potential difference therebetween to a second driving voltage and applies the second driving voltage to a lamp.