Based on animal protein and microbiological protein foaming agents, the biological foaming agent was prepared by mixed with cetrimonium bromide(CTMAB). The effect of CTMAB content on the foam properties of biological foaming agent was investigated. Based on these work above, the effects of two kinds of biological foaming agents on the macro properties and microstructure of foam concrete were studied. The results show that the optimum content of CTMAB for animal protein based foaming agent(A type) and microbial based foaming agent(M type) are 0.7% and 0.5% respectively. The foam diameter distribution from M type foaming agent is uniform and the size is small, which leads to better stability of M type foaming agent than that of A type foaming agent. The pore size distribution in the M type foam concrete is uniform and the size is small, the calcium to silicon ratio of the hydration generated C S H is relatively small, and the hydration product is compact. Therefore, the compressive strength(3.3MPa) is higher than that of the A type foam concrete(2.1MPa).