本文以臺灣市值前4大之上市ETF為研究樣本,包含元大台灣卓越50證券投資信託基金(證券代號:0050)、元大台灣高股息證券投資信託基金(證券代號:0056)、國泰台灣ESG永續高股息ETF基金(證券代號:00878)及富邦台灣釆吉50基金(證券代號:006208),探討臺股開放盤中零股交易(2020年10月26日),盤中零股成交股數對於未來報酬率之相關性及可預測性,以迴歸模型分析。實證結果發現,在盤中零股的成交股數較低的交易日買進,未來可獲得的報酬顯著較高,相反的,在交易股數較高的交易日買進,則後續會獲得較差的報酬,意即在投資人情緒較低的時候買進,未來股價反轉向上的可能性較高,而在投資人情緒高昂的時候買進,容易因為投資人反應過度,導致過度推升股價,造成未來股價反轉向下的可能性較高。;This article uses the top 4 listed ETFs in Taiwan in terms of market capitalization, including Yuanta/P-shares Taiwan Top 50 ETF (stock code: 0050), Yuanta Taiwan Dividend Plus ETF (stock code: 0056), Cathay MSCI Taiwan ESG Sustainability High Dividend Yield ETF (stock code: 00878) and Fubon FTSE TWSE Taiwan 50 ETF (stock code: 006208) as the sample: The results of the empirical analysis were that buying on the trading day when the number of Odd Lot traded in the ETF is lower will result in a significantly higher return. On the contrary, buying on a trading day with a high number of shares traded will result in a poorer payoff, meaning that buying at a time when investor sentiment is low will result in a higher probability of upward stock price reversal, while buying at a time when investor sentiment is high will result in a higher probability of downward stock price reversal due to an overreaction by investors, which will lead to an excessive push in stock price.