The preparation of mesoporous zirconia with high surface area, large and tunable pore size and enhanced high thermal stability by controlled sol-gel method and post-synthesis treatment with aqueous ammonia was reported. The effects of preparation parameters, such as pH, aging temperature and the mole ratio of diglycol/zirconium (IV) n-propoxide on properties of the mesoporous materials were systematically investigated. It was found that the resultant materials possessed BET surface area as high as 406 m2·g−1 and pore sizes ranging from 3.2 nm to 17.8 nm. Furthermore, the sample prepared at pH 2.4 and 40°C showed high thermal stability. After calcination at 700°C for 4 h in air, the obtained material gave BET surface area of 195 m2·g−1, and pore size up to 15.0 nm.