Firm merger has recently become one of the most important strategies for modern firms and multinational firms to expend and improve their competitive strength and outmatch their rivals. Meanwhile, firm merger also becomes a strategic fool for a country to adjust industry structure and guarantee social welfare. 企业兼并已成为现代企业和跨国公司实现向外扩张、增强竞争实力和战胜竞争对手的一种重要战略手段,同时也是一个国家调整产业结构,保障社会福利的战略性工具。