金融业已成为经济增长的关键点。健全的金融体系是经济的有力保障。然而，不良贷款的存在影响了金融制度的健康发展，同时，该问题也引起了学术界与政府当局的关注。 因此，兼并与收购能否通过经济规模消除不良贷款与已关闭的无效益项目的不利影响引起了学术界的广泛讨论。通过最新的效率限界法与金融分析法，本论文在现有经济、管理与金融的理论基础上阐述了兼并与收购能否减轻不良贷款的影响。在开头部分，本论文就中国银行业存在的问题进行了探讨，并对兼并与收购的优势做了分析，认为两者都是用于提高效率。在对该课题先前的研究做过分析与比较后，本论文提出了关于银行兼并与收购的意见：一方面主要是建立Translog成本函数模型以通过使用效率限界法分析中国某些银行的成本效率，另一方主要是利用金融数据来研究利润效率。两个方法都得出了相同的结果，亦即，国有银行在合并后得到了效率的提升，但股份制商业银行并未有变化，因此其无法吸收不良贷款翻译公司。

Financial developments have become the key role in economic growth. Healthy financial system is one of economic growth’s necessary conditions. But the problems of non-performing loans weakens the financial system’s healthy development, which attracts the academic community’s and political much attentions. Under this background, whether mergers and acquisitions can make economies scale to absorb the adverse effect of non-performance, and closed down non-valuable projects becomes an important topic in academic field. On the basis of theories in economy, management and finance, and using the latest efficient frontier approach and financial analysis approach, this paper aims to analyze whether the roles of mergers and acquisitions can ease the problems of non-performing loans. The paper first discusses the problems of banking sector in China, and then looking at the advantages of mergers and acquisitions and finds that both of them are for efficiency improving. After reviewing and comparing the former study concerned this side, we give our thought for bank mergers and acquisitions: one major part use the efficient frontier approach by establishing the trans log cost function model to analysis the cost efficiency from some Chinese banks, the other major part use finance data to study profit efficiency. The two method could give the same result, it show that  the state–owned banks do have efficiency increase after merger, but share holding commercial banks are not, therefore, it is unable to absorb non-performing loans.