媒體集團化與媒體產權集中成為傳播產業發展趨勢後，傳播學術研究領域愈發重視媒體產權集中對媒體產製內容多元性的影響。近年來台灣無法自外於全球傳播產業匯流趨勢，不僅媒體集團持續擴張，產權集中情形亦益發明顯，從東森媒體集團到中時媒體集團，各媒體集團透過市場的垂直與水平整合，逐步發展成跨媒體的集團巨獸。本研究透過內容分析法，檢視中時集團併購中天電視，以及東森集團併購民眾日報前後各一年，中國時報對中天電視節目，以及民眾日報對東森電視節目等相關報導，其「量」與「質」的變化是否達顯著的差異。研究結果發現，當中天電視成為中時集團成員，以及民眾日報成為東森媒體集團成員後，中國時報對中天電視，以及民眾日報對東森電視等相關報導的「量」與「質」都有顯著的增加，相對而言則使非集團媒體企業相關的報導大大的減少，顯示出媒體集團化與產權集中確實對媒體內容多元化有顯著的影響。

The concept of diversity has been a long term subject for exploration to various theoretical disciplines in social science. For media research, concerns on media diversity need to be reconsidered due to the world wide inevitable trend of media conglomeration and ownership concentration, as well as media convergence. This study conducted a content analysis to investigate the influence of ownership concentration on media content diversity. The China Times Group acquired CTi (a satellite television) in 2002, and EMC acquired Ming-Chung Daily in 2000. The major focus of this study was the changes and differences in terms of content quantities and qualities before and after their acquisitions. The results indicated that media ownership concentration has significantly increased the content quantity and reporting quality regarding their mother companies’ media.