The mesoporous anatase form of TiO2 was prepared by modified sol-gel method using ionic liquid as a template agent. The prepared nanosize TiO2 particle was characterized by N-2-physisorption, XRD, TEM, and SEM. The physical properties of prepared TiO2 particles were compared with that prepared by conventional sol-gel method without template. It has been proved that the anatase phase prepared by modified sol-gel process using ionic liquid was preserved well even if the TiO2 samples were treated at high temperatures up to 800 degrees C while those prepared by conventional sol-gel method were transformed from anatase to rutile phase gradually during calcinations at 600 degrees C. Moreover, there was no phase transition in the sample obtained by sol-gel method with ionic liquid in spite of prolonged calcination for 60 h at 600 degrees C. However, in case of those samples prepared by conventional sol-gel method, the portion of rutile form was continuously increased with the increase in the calcination period.