PROBLEM TO BE SOLVED: To provide an endoscope light source device and endoscope system capable of reducing the light intensity of a wavelength band equal to or higher than 460 nm and equal to or less than 500 nm without enlarging the device structure.SOLUTION: A first DM 55a is arranged between a V-LD 53 and a rotary fluorescent body 50, passes excitation light LE emitted from the V-LD 53 to be radiated to the rotary fluorescent body 50, and reflects a component in green light LG generated in the rotary fluorescent body 50 that travels toward the V-LD 53. Second to fourth DMs 55b-55d arranged on the opposite side of the V-LD 53 viewed from the rotary fluorescent body 50 respectively reflect blue light LB, red light LR, and violet light LV and pass the green light LG. The fourth DM 55d among the second to fourth DMs 55b-55d has notch characteristics to reduce the light intensity of a wavelength band equal to or higher than 460 nm and equal to or less than 500 nm.
