本文探討台灣主併公司採用不同購併支付方式，其購併前財務特質的決定因素及其購併後財務特質的變化。利用Logit迴歸模型，我們發現影響不同支付方式的財務特質為企業規模、發達收入成長性及購併對象國別等因素。當主併公司之規模愈小，成長率愈低且購併對象為國外企業，則偏向採用現金購併。反之，則偏向採用股票購併方式。經比較購併前後財務特質的變化，我們發現購併使財務流動性提高、企業規模變大及財務槓桿度降低，此等有利於管理者，而活動力、獲利性及成長性大幅下降，則有害於股東，因此Roll（1986）的自大假說與Jensen （1986）的自由現金流量假說所強調的代理問題確實存在。將購併依支付方式分為股票員走併與現金購併兩種，我們發現現金購併比股票購併對企業財務特質的負面影響為大。再將現金購併細分為國外現金購併及國內現金購併兩類，經去除國外因素後，我們發現國內現金購併較股票購併（全為國內）對企業財務特質的負面影響為小，甚至於有正面影響。此點吻合Myers& Majluf（1984）及Fishman (1989)之資訊不對稱理論。而國外現金購併對企業經發之不利影響，則值得欲從事海外購併者戒之，或許「謀定而後動」方為良策，否則「呷緊會弄破碗」。但國內購併者似可利用現金支付方式傳達給市場正面的好消息，當然利用股票換股方式即為負面的壞消息。若就國內與國外購併相較，國外購併顯然對股東較為不利，亦即代理問題更為嚴重。

　　This paper examines the determinants of the medium of exchange and its effect to Taiwan's acquiring firm characteristics. Using Logit regression model, we find that the determinants of the medium of exchange are firm size, sales growth and the country of the target firm. The smaller acquirer's size, the lower growth rate and the foreign target firm make the Taiwan's acquiring firms choose cash-exchanged M&As. Otherwise they choose stock-exchanged M&As. Comparing the change of firm characteristics prior or posterior to M&As, we find higher liguidity, larger size and lower leverage ratio which are good for managers, and the declining activity, profitabi1ity and growth rate which are bad for shareholders. These results show that the agency problem of Roll’s (1986) hubris hypothesis and Jensen’s (1986) free cash flow hypothesis does exist. When we consider the effect of the medium of exchange we find that cash- exchanged M&As have worse performance in firm characteristics than stock- exchanged M&As. Deleting the poor effect of international cash­exchanged M&As， the result shows that domestic cash-exchanged M&As have done better than domestic stock-exchanged M&As. This is consistent with the theory and evidence of information asymmetry of Myers & Majluf (1984) and Fishman (1989). Finally we find that international M&As have worse agency problem than domestic M&As.