The utility model provides an optical fiber maintaining device and an endoscope system, wherein the optical fiber maintaining device can reduce transmission loss and prevent an insertion core arranged on an optical fiber and a refractive index gradual change collimator from being damaged, and the optical fiber maintaining device is utilized by the endoscope system. The optical fiber maintaining device (68) arranged in a light source device is provided with a first GI collimator (71), a first insertion core (72) fixedly connected with a first optical fiber (54), a maintaining tube (73), a thread component (74), a spiral spring (75) and a press component (76). The front end side of the maintaining tube (73) is fixed to the first GI collimator (71). The first insertion core (72) is contained at the back of the first GI collimator (71). The base end portion of the maintaining tube (73) is provided with the thread component (74) in a threaded mode. The spiral spring (75) and the press component (76) are contained in the thread component (74). The spiral spring (75) exerts force to enable the press component (76) to press the first insertion core (72) towards the first GI collimator (71), and the press component (76) is clamped and stopped by the maintaining tube (73) and is limited to rotate around a shaft.
