Machine learning provides new perspectives and methods for company M&A valuation due to its powerful data processing and prediction capabilities. This paper analyzes the prediction steps based on the decision tree algorithm, i.e., decision tree generation, attribute selection, decision tree construction, and accuracy metrics, and obtains the relevant data of AB after merger and acquisition through data mining. The model and SHAP framework are utilized to predict the financial risk, financial performance, and enterprise value of the two post-merger companies. The precision, recall, and F1 scores of this paper’s model range from 91.25 to 93.81, which has a good performance of company M&A valuation. This paper’s model predicts that in 2024, the key indicator of AB’s financial crisis is Gross margin, which has an importance of 0.297, and the possibility of AB’s financial crisis increases when the value of Gross margin is between -0.0279 and -0.0014. The accuracy of the financial performance prediction of this paper’s model is more than 0.97, which can accurately value the company’s performance. The model in this paper predicts the enterprise value of AB in 2024 to be 52.14yuan/share, respectively.