本研究旨在探討台灣股市庫藏股買回宣告對股票報酬的影響;研究期間為 2017 年2020 年;以台灣上市公司為研究樣本,透過事件研究法來分析不同產業公司及不同買回目的之庫藏股買回宣告對其股價報酬率之影響。實證結果顯示,在平均異常報酬率方面,電子類股、生技醫療類股、傳統產業類股及不同買回目的在宣告日股價均具有正向之宣告效果,而在平均累計異常報酬方面,以維護公司信用及股東權益為買回目的之宣告效果大於以轉讓股份予員工為目的之宣告效果。 The purpose of this study is to explore the impact of the announcement of treasury stock buybacks in the Taiwan stock market on stock returns; the study period is from 2017 to 2020 the research samples of Taiwan listed companies are used to analyze the treasury of different industry companies and different buyback purposes about the effect of the announcement of share repurchase on its stock price return through the Event Study Method. The empirical results show that in terms of average abnormal returns, electronic stocks, biotech medical stocks, traditional industry stocks and different buyback purposes all have positive announcement effects on the announcement date. In terms of average cumulative abnormal returns, the effect of the announcement for the purpose of maintaining the company's credit and shareholders' equity is greater than the effect of the announcement for the purpose of transferring shares to employees.