To provide a method and an apparatus for removing radioactive cesium from waste containing radioactive cesium at low cost. A radioactive cesium removal apparatus 1 including: an incinerator 22 for burning an inflammable waste polluted with radioactive cesium; a suspension preheater 23 for, with the combustion exhaust gas G5 and a sensible heat of the incineration ash of a combustible C discharged from the incinerator, generating calcium oxide or/and magnesium oxide from a source of calcium oxide or/and a source of magnesium oxide, cyclones of the suspension preheater being arranged in multistages; a rotary kiln 21 for burning an inorganic substance S polluted with radioactive cesium together with the calcium oxide or/and the magnesium oxide and the incineration ash D3 including the radioactive cesium; and collectors 31, 32 for collecting cesium volatilized in the rotary kiln.