The present invention provides a discharge lamp driving device, a light source device, a projector, and a discharge lamp driving method, which can improve the life of the discharge lamp regardless ofindividual differences of the discharge lamps. According to one embodiment of the invention, the discharge lamp driving device is characterized in that the discharge lamp driving device includes a discharge lamp driving unit that supplies a driving current to a discharge lamp having a first electrode and a second electrode; a control unit that controls the discharge lamp driving unit; and a storage unit that stores a plurality of drive modes of the drive current, and the control unit selects one of the plurality of drive modes based on the machine learning, and executes the selected drive mode, and if a predetermined condition is satisfied, The control unit does not select and execute the machine learning-based drive mode, but performs a predetermined drive mode among the plurality of drive modes.