本研究係以1997年至2006年期間曾放股票股利或現金股利之台灣上市上櫃公司為研究對象,運用各種不同的異常績效衡量方法與基準報酬的選取,來探討股利結構變化對公司長短期投資績效之影響。 研究結果顯示:台灣上市櫃公司股利結構發生變化後,在短期確實存在異常績效,且投資人對公司之股利決策多數是抱持正面之評價。其中,在三種不同的事件日中,特別是於除權(息)日前後投資者容易有較大動作的部位調整行為,其次股東會決議日又比董事會決議日,其投資者表現來的強烈與顯著,顯示投資者對於公司股利政策確實於股東會正式召開宣告後,股價才會在市場上產生較積極的反應效果。 符合效率市場假說,本研究於長期實證中,普遍結果顯示並無統計顯著異常績效之行為。 This article uses the different methods of the unusual performance and benchmark returns to analyze the effect of the dividend structure changing for the investment performance during the long run and short run of the Taiwan listed firms which have ever payout the stock dividend or cash dividend during the period 1997 to 2006. Our empirical findings are as follows: The abnormal return exists in the short-term after the changing of dividend structure of Taiwan listed firms, and most of the investors have commended about the dividend decision. In the three kinds of event date, especially on ex-dividend day, the investors will adjust their holding substantially; moreover, the stockholders’ meeting authorized date are more significant than the approval date of the board meetings. The empirical shows that the dividend policy will result in positive response of price after the stockholders’ meeting authorized. The long run empirical results indicate no significantly unusual performances, and the market efficiency hypothesis holds on the market.