采用溶胶凝胶技术在石英玻璃基片上制备钛酸铋薄膜，讨论了前驱体溶液的酸碱度（ｐＨ值）对薄膜结构和结晶性的影响．ｐＨ＜２和ｐＨ＞３５的前驱体溶液所制备的薄膜在晶化过程中出现Ｂｉ２Ｔｉ２Ｏ７和Ｂｉ２Ｔｉ４Ｏ１１杂相．ｐＨ＝２５～３５的前驱体溶液制备的薄膜是钙钛矿Ｂｉ４Ｔｉ３Ｏ１２结构的取向薄膜 The bismuth titanate thin films were prepared by sol-gel technique on the quartz glass substrate. The influence of the pH value of the precursor solution on the structure and crystallinity of the films was also discussed. Bi2Ti2O7 and Bi2Ti4O11 hetero-phases appear in the crystallization process of the films prepared by precursor solution with pH <2 and pH> 3.5. The film prepared by the precursor solution with pH = 2.5 ~ 3.5 is the oriented film of perovskite Bi4Ti3O12 structure