The study of the effects of nano-carbonate burning rate catalysts on the pressure exponent,heat of explosion and mechanical properties of the AP/Al/HTPB propellants were conducted. The results show that the catalyst can reduce the burning rate pressure exponent of the propellants to 0.20 in the pressure ranges of 4-10 MPa and 10-18 MPa. The combustion efficiency and the heat of explosion of the propellants increase as the increasing of the content of the nano-catalyst. It also shows the nano-catalyst has some effects on the mechanical properties and processing properties of the propellants. It has found that the suitable weight fraction of nano-carbonate catalyst in the propellants is 0.5%-1%.