A discharge lamp driving device includes a discharge lamp driving section configured to supply a driving current to a discharge lamp, the driving current being an alternating current for driving the discharge lamp, and a control section configured to control the discharge lamp driving section. The control section controls the discharge lamp driving section such that the driving current having a driving frequency different from a natural frequency of the discharge lamp and a frequency of 1/2n (n is a natural number) times the natural frequency is supplied to the discharge lamp.