PROBLEM TO BE SOLVED: To provide a light source device for endoscope, an endoscope system, and an operation method thereof capable of improving a red image in quality and providing a high quality observation image by a color emphasis processing.SOLUTION: A light source device includes a first light source to emit red light LR, a second light source to emit green light LG, and a third light source to emit blue light LB. A light source control controls an emission timing of the light source device to emit the red light LR independently without overlapping at least one of the green light LG and the blue light LB for shorter emission time than the green light LG or the blue light LB. In addition, the light source control controls an emission intensity of the light source device such that an emission intensity of the red light LR is greater than that of the green light LG or the blue light LB. An imaging control conforms light-receiving periods of an imager for the red light LR, the green light LG, and the blue light LB to light-emission periods for the red light LR, the green light LG, and the blue light LB, respectively.SELECTED DRAWING: Figure 7
