Enterprises must have a deep understanding of the financial risks of M & A in order to better identify and prevent. The definition of M & a financial risk can be divided into narrow sense and broad sense. In a narrow sense, the financial risk of M & a generally refers to the debt repayment risk caused by the financing decision-making behavior; in a broad sense, it refers to the uncertainty of M & A caused by the change of capital structure, deterioration of financial situation or loss of financial achievements caused by the various financial decisions of M & A, and it is the financial dilemma caused by the serious negative deviation between the expected value and the actual value of M & A And financial crisis.