中文摘要：

会计稳健性作为一项重要的会计信息质量要求，一直受到会计准则制定者和会计信息需求者的重视。文章以2005-2008年沪市A股上市公司为研究样本，采用了改进后的Basu模型，对会计盈余及时性，反转性以及新会计准则实施对会计盈余稳健性的影响进行了实证分析。研究结果表明，新会计准则实施后，我国上司公司盈余稳健性有所提升，但提升的幅度有限，因此，单纯依靠会计准则的变革并不能实质性的改善会计信息的质量，只有进一步完善与准则相配套的法律法规和执行机制，才能使会计准则变革提高上市公司会计准则的质量。

英文摘要：

As a reflect of accounting information quality, the accounting conservatism is highly val- ued by the accounting standards makers and accounting information demanders Based on the sample of the Shanghai A - share listed companies during 2005 to 2008, we use the improved Basu model to empirically analyze the influence of timeliness and reversibility of accounting earn- ings on the earnings conservatism, as well as how the change of accounting standards affect it We find that, after the implementation of new accounting standards, the earnings conservatism of China＇s listed companies has improved but with a limited range. Therefore, solely depending on the innovation of accounting standards can＇t substantially improve the quality of accounting infor- mation. Only the further improvement of regulations and enforcement mechanisms matched with the standards can help the changes improve the quality of accounting standards in China＇ s listed companies.