Paraffin emulsion, silicone emulsion and styrene-acrylic emulsion have been used respectively to modify the foamed cement boards by two different ways, namely, immersion adsorption and vacuum adsorption. The results show that the adsorption effect of pressure reduction adsorption is better than that of immersion adsorption, with the adsorption rate of foam cement boards positively related to the mass fraction of solid substance in polymer emulsion. In addition, for the three kinds of emulsion, the paraffin emulsion has a great influence on the volume absorption rate of the foamed cement boards. The volume water absorption of paraffin modified foam cement plates is 8.9%, about 40.6% lower than that of 2.4%. The adsorption of silicone acrylic emulsion or styrene acrylic emulsion on foamed cement boards helps to improve the compressive strength. The compressive strength of the foamed cement boards increases to 0.624 MPa after the modification of the silicone acrylic emulsion, an increase by approximately 51.4%; while after the modification of styrene acrylic emulsion, the compressive strength of the cement boards increases to 0.527 MPa, an increase by approximately 27.9%.