Abstract: Foam aluminum with high porosity (>80%) and small diameter pores was prepared with the calcium as tackifier,TiH2 as foaming agent and aluminum as matrix.Effects of oxidizing of TiH2,mixing time,addition of TiH2 and foaming time on the pore structure had been studied.Compressive tests were performed.The results show that oxidizing treatmant led to decrease of the decomposition rate of TiH2 and foam aluminum with smaller diameter pores was obtained with the same foaming time.More TiH2 should be added in preparing foam aluminum with the same porosity compared with the untreated TiH2.Extending the mixing time was prone to obtain small pore foam aluminum.Under the same condition,the diameter and porosity increased when the time increased.The foam aluminum with smaller pore size had higher uniaxial compression stress-strain yield platform and energy absorption as the porosities were similar.