The amount of heat generated at a light input portion of a light guide for endoscopes constituted by a plurality of bundled optical fibers is suppressed. The light guide for endoscopes is constituted by a plurality of bundled optical fibers, for propagating an illuminating light beam, which is focused and caused to enter a light input end facet thereof, to a light output end facet thereof, to emit the illuminating light beam onto a portion to be observed. A transparent member having a sectional shape which is at least as large as the focused spot of the illuminating light beam is provided in close contact with the light input end facets of the optical fibers. The optical fibers are connected to the transparent member in a maximally densely packed state.