中文摘要：

预约披露制度是与披露时间相关的一项重要规范，其目的在于提高定期报告披露的均衡性，但预约披露时间的变更与管理者选择披露时机的行为密切相关。本文以沪、深股市上市公司年报预约披露制度的执行情况为研究对象，时间涵盖2001-2004年四个可获得数据的年度。通过实证分析，我们发现：（1）未预期盈余越低，公司越可能延迟披露年报时间，并且未预期盈余为负的公司相对未预期盈余为正的公司延迟披露的可能性较大；（2）亏损公司和年报被出具非标意见的公司倾向于延迟披露年报，而且非标审计意见的严重程度越高，延迟的可能性越大。

英文摘要：

Precontracted disclosure system is an important norm with disclosure time related, and its purpose is a behavior that to increase periodical balance of report disclosure. But the periodical report precontracted disclosure date change maybe related to the manager＇s timing alternation, This text begins with all of A-share listed-companies annual financial reports precontracted disclosure system that carried out at Shang-hai and Shen-zhcn Security Markets as research object, time covers four years which can acquiring data of year 2001-2004.Through the empirical analysis, we found that： （ 1 ）the lower unexpected profits of listed-companies, the more tend to delay their annual report, and this is the same to companies with negative unexpected profits; （ 2 ）companies with losses and unqualified audit opinions tend to delay their annual report, and the worse degree of unqualified audit opinions, the possible of disclosure delaying is bigger.