A scanning endoscope system has a light guide portion that guides an illuminating light, a drive portion capable of causing the light guide portion to swing so that an irradiation position of the illuminating light draws a locus corresponding to a predetermined scanning pattern, a light detecting portion that receives a return light of the illuminating light and outputs a signal, a control portion that drives the drive portion to perform scan so that the irradiation position of the illuminating light becomes a locus in a spiral shape, and an image generating portion that generates an image of an object based on a signal outputted from the light detecting portion in a predetermined timing, wherein the control portion further performs control for driving the drive portion so that the irradiation position of the illuminating light circles on a same circumference in the predetermined timing.
