A laser light source device which is used for a video display device displaying video by using plural image frame data inputted from an image generating device includes a laser light source emitting laser light, a drive circuit driving the laser light source, a target light amount acquisition unit that acquires a target light amount which is a light amount necessary for displaying the image frame data, an output light amount detecting unit that detects an output light amount of the laser light source device, a control unit that controls the drive circuit so that the output light amount will be the target light amount, and a determination unit that determinates deterioration of the laser light source by using drive conditions of the drive circuit with respect to at least two different target light amounts at the time of control.