The results of studies of light-induced magnetic phase transitions in mixed-valence manganese oxides, namely in manganites and garnets, are presented. The visible light induces the phase transition in the (Pr,La,Ca)MnO3 manganites from an insulating antiferromagnetic (AFM) state to a metallic ferromagnetic (FM) one. In the AFM garnet Ca3Mn2Ge3O12, the illumination with linearly polarized visible light changes the field of metamagnetic (MM) phase transition induced by a magnetic field. The mechanisms responsible for the photoinduced phenomena in mixed-valence manganese oxides are discussed. Effect of light on the magnetic phase transitions is related to the photoinduced charge transfer between Mn3+ and Mn4+ ions placed in nonequivalent positions of crystal lattice.