We have found charge ordering in perovskite-type manganese oxides at low-carrier-doping region in neutron diffraction experiments. In La1-xSrxMnO3 (x = 0.1 and 0.15), we observed superlattice reflections at commensurate positions and the onset temperature Tp of the superlattice structure coincides with the low-temperature metal-toinsulator transition point. Pr1-xCaxMnO3 compounds are also studied at the stoichiometric concentration of x = 0.25. We observed diffuse satellite peaks indicating the existence of new charge-ordered state at this concentration. © 1998 Elsevier Science B.V. All rights reserved.