PROBLEM TO BE SOLVED: To provide an endoscope light source device, an endoscope system, and an operation method of the endoscope light source device capable of adjusting a contrast of a blood vessel flexibly, according to depth and thickness under a mucosa.SOLUTION: An endoscope light source device comprises: a V-LED 20a for emitting V-light having a depth resolution with respect to a blood vessel under a mucosa which is an observation target a B-LED 20b for emitting Bs-light having a thickness resolution with respect to blood vessels under the mucosa and existing at a depth equal to a depth where the blood vessel as the observation target exists a Bs-light generation band restriction filter 25 a light amount ratio setting part 23 for setting a light amount ratio of the V-light and the Bs-light, and setting a blood vessel contrast to the mucosa to a target contrast corresponding to the depth and thickness of the blood vessel and a light source control part 22 for controlling the V-LED 20a and the B-LED 20b using the light amount ratio set by the light amount ratio setting part 23.SELECTED DRAWING: Figure 16
