In a light irradiating device of a scanning endoscopic device, a proximal end of a lens optical system is located apart from a distal end of the optical fiber in a distal direction by a first dimension, and a lens-side facing portion of a lens-side cylindrical portion faces a fiber-side facing portion of a fiber-side cylindrical portion apart from the fiber-side facing portion in the distal direction by a second dimension smaller than the first dimension. An inner peripheral end of the lens-side facing portion is located to an inner peripheral direction side of an outer peripheral end of the fiber-side facing portion, and an outer peripheral end of the lens-side facing portion is located to an outer peripheral direction side of an inner peripheral end of the fiber-side facing portion. The proximal end of the lens optical system and the distal end of the optical fiber are located between a distal end and a proximal end of the window in directions parallel to the longitudinal axis.
