Abstract: The mechanical properties of porous cement concrete were studied in the paper. The effects of water-ash ratio, porosity, grading, silica fume, and cinnatnene-acrylate on compressive and flexural strength of the mixture were investigated as well. The results showed that the compressive and flexural strength of the mixture increased into one extenl firstly,then decreased with water-ash ratio increasing. The strength of the mixture decreased obviously with porosity increasing. Changing grading and adding strengthing agent (silica fume and cinnamene-acrylate) took effects on the strength of the mixture. The study was helpful to the composition design of porous cement concrete.