An R-Fe-B-based, sintered magnet, wherein R is one or more of rare earth elements including Y, is produced by the method including the steps of mixing fine R-Fe-B-based magnet powder with a mineral oil and/or a synthetic oil having a fractional distillation temperature range of 150.degree.-400.degree. C. and a kinetic viscosity of 10 cSt or less to prepare a mixture; charging the mixture under pressure into a die cavity equipped with a filter, to which an orientated magnetic field is applied, while removing a mineral oil and/or a synthetic oil from the mixture; compressing the mixture in the die cavity to carry out a wet molding while orientating the powder to prepare a green body; heating the green body to a temperature up to 500.degree. C. at a speed of 10.degree. C./min or less under pressure of 10.sup.-1 Torr or less for 30 minutes or more to remove a mineral oil and/or a synthetic oil from the green body; and then sintering the green body.