The invention discloses a medical garbage incinerator. The medical garbage incinerator comprises a gasification combustion chamber and a mixing combustion chamber, wherein a hand wheel, a furnace door, a connecting rod and a movable shaft are arranged on the gasification combustion chamber; the right upper side of the gasification combustion chamber is fixedly connected with an electric control box; a combustor is arranged below the electric control box; the combustor is fixedly connected to the middle lower side of the right side of the gasification combustion chamber; an after-combustion dust removal chamber is fixedly connected above the gasification combustion chamber; a dust clearing door is arranged in the middle of the after-combustion dust removal chamber; the left side of the after-combustion dust removal chamber is equipped with the mixing combustion chamber; a secondary combustor and a thermoelectric valve are arranged on the mixing combustion chamber; the left side of the gasification combustion chamber is equipped with a base, a fan, an air inlet tube and a control valve; the upper end of the after-combustion dust removal chamber is fixedly connected with a flue gas purifying chamber; the middle part of the flue gas purifying chamber is movably connected with a flue gas filter furnace door; and the upper end of the flue gas purifying chamber is fixedly connected with a chimney. The medical garbage incinerator is totally sealed, is small in size, and is high in incineration efficiency.