The La(FexSi1-x)(13) compounds exhibit large magnetocaloric effects (MCEs) due to the itinerant-electron metamagnetic (IEM) transition. By hydrogen absorption, the Curie temperature T-C increases up to room temperature with retaining the IEM transition. The La(Fe(0.9)Sio(0.10))(13)H-1.1 compound indicates a large isothermal magnetic entropy change of Delta S-m = -28 J/kg K at 287 K in the magnetic field change from 0 to 2T (Delta B = 2T). In addition, the MCEs are enhanced by partial substitution of Ce for La. The value of T-C for La(FexSi1-x)(13) is decreased by partial substitution of Mn for Fe, keeping excellent MCEs. Consequently, the La(FexSi1-x)(13) and their modified compounds are promising as magnetic refrigerants working at a wide range of temperature covering room temperature.