In this paper, pre-synthesized MgTi₂O₅ and MgO+2TiO₂ in-situ synthesized MgTi₂O₅ were introduced as the additives required for the preparation of aluminum titanate ceramics, and the effect of MgTi₂O₅ on the phase composition and properties of aluminum titanate ceramics was studied. The results show that MgTi₂O₅ or MgO+2TiO₂ can promote the synthesis of aluminum titanate at low temperature by forming solid solution, the addition of a small amount of MgTi₂O₅ can effectively promote the synthesis of aluminum titanate crystals at a lower temperature. When the MgO content is 2% (mole fraction), the synthesis rate of aluminum titanate added with MgTi₂O₅ at 1 300 ℃ is 28.4 percentage point higher than that of MgO+2TiO₂. On the premise of similar synthesis rate of aluminum titanate, the firing temperature of adding MgTi₂O₅ is lower than that of adding MgO+2TiO₂. When 6%MgTi₂O₅ is added, the thermal expansion coefficient of the ceramic samples fired at 1 280~1 350 ℃ is between -0.11×10^-6℃^-1 and 0.58×10^-6 ℃^-1. With the increase of firing temperature, due to the anisotropy and overgrowth of crystal, the microcracks inside crystal are easy to reduce the flexural strength of obtained aluminum titanate ceramics.