The invention particularly relates to a foamed dement mixing device which comprises a mixing device main shell, and a material blocking plate which is inserted in the mixing device main shell, wherein the material blocking plate is arranged at the upper part of the mixing device main shell; an upper cement paste inlet and a lower foam inlet are formed in the upper part and the lower part of the material blocking plate; a foamed cement outlet is formed in the lowest part of the material blocking plate; a plurality of discharging holes are formed in the material blocking plate. The foamed dement mixing device has the advantages that the foam loss rate is small, the structure is simple, light and smart, the carrying is convenient, the construction cost is low, a power source is not required, energy is saved, the environment is protected, and the proportion can be adjusted and controlled randomly.