購併是企業重要的決策之一，而會引發企業選擇購併決策的因素一直是學者研究的議題之一，本研究利用民國80年1月1日至93年12月31日間所發生的購併案件為研究樣本進行分析，從研究分析中我們可以得到下列結果：
1.當企業ROA、ROE越佳時，企業執行購併的機率越大。
2.當企業擁有較低的負債比率時，執行購併的機率就越高。
3.當企業成長率較高時，執行購併的機率就越大。
4.當企業處於較不競爭的產業，執行購併的機率就越大。
5.當內部人持股越多、法人持股越多或股權越集中的情況下，企業執行購併的機率就越大。
除了研究這些因素與購併決策間的關係外，本研究亦試著檢驗購併前的因素是否對企業購併後的長期績效有影響，期許能夠建立一個對於購併後主併企業績效預測的模型，而以下便是我們所得到的結論：
1.購併前的經濟因素對於企業購併後的Tobin’s Q有顯著的影響。
2.企業在購併前的成長率越高，其購併後長期績效指標將會下降。
3.如果企業所存在的產業越競爭，則企業購併後的相對於產業平均長期績效將會提升。
4.當購併前的資產報酬率與淨值報酬率越佳時，其長期反而會因購併案件的執行而使得績效下降。
5.企業在購併前擁有越多的自由現金流量時，其績效將會越好。

This research tried to find out those important factors that affect mergers and acquisitions. The paper had been divided into two parts.
First, we tried to find out the important effective factores that influence company’s acquisition strategies. There are five significant identifications of acquiring firms: 1. better ROA, ROE; 2. lower Debt Ratio; 3. higher Growth Rate; 4. participating in less-competive industry; 5. equity structure is more concentrative.
Second, we examined those factors whether influencing the long-term efficiency of the acquiring firm or not. There are also five significant results: 1. the economic factors will effect the long-term Tobin’s Q of the acquiring firm; 2. when the company is in the growing stage, the efficiency will be decresed after the acquisition; 3. if the industy is more competive, the acquiring firm will gain more profit after the acquisition; 4. merger and acquisition events will cut down well-performed firms’ efficiency; 5. the more free cash flow the acquiring firm has before merger and acquisition, the better improvement it will have.

中文文獻
1.李佳伶（2003）。公司法人股東與經營績相關性之研究。國立臺灣大學財務金融學研究所碩士論文，未出版，台北市。
2.吳家昌（2004）。產業景氣與購併績效之研究。國立政治大學企業管理研究所碩士論文，未出版，台北市。
3.黃榮龍（1993）。股權結構與經營績效之研究。國立政治大學會計研究所碩士論文，未出版，台北市。
4.詹雅慧（2005）。股票購回與現金股利政策變動宣告效果之研究：以台灣上市電子公司為例。國立臺灣科技大學財務金融研究所碩士論文，未出版，台北市。
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