To provide a discharge lamp device capable of accurately detecting leakage of a heat conductor from an electrode.

In the discharge lamp consisting of a discharge lamp 10 oppositely arranging a pair of electrodes inside an arc tube enclosed with a light-emitting material, wherein at least one electrode of the discharge lamp 10 is formed by an electrode forming an airtight space in the inside and a heat conductor enclosed in the airtight space and made from metal having a melting point lower than that of metal forming the electrode, and a measuring means 30 for watching a lighting-up state of the discharge lamp 10, the measuring means 30 measures emitting light emitted from the light-emitting material of the discharge lamp at fixed intervals in sequence, and compares a measured value of the latest emitting light with the measured value of the past emitting light when setting a fixed time interval rather than the measured time of the latest emitting light in sequence, and has a detection means 34 for detecting changes of the measured values.