Based on the limitations of existing studies, this paper examines the relationship between information disclosure and M&As and the impact of potential moderating variables from the aspects of capital market valuation efficiency and M&A performance. Meta-analysis is used to summarize and analyze 59 effect values extracted from 59 empirical literatures. The results show that:（1）Information disclosure can effectively improve the efficiency of capital market valuation. Specifically, information disclosure can reduce the synchronization of stock prices, enhance market liquidity, and reduce the cost of capital.（2）Information disclosure can also improve M&A performance.（3）The relationship between information disclosure and M&As is also affected by enterprise size, analyst tracking and measurement dimensions.
The contributions of this paper are as follows: Firstly, the existing research results on information disclosure and M&As have significant differences in the correlation direction and strength degree, the influence of situational factors and measuring factors on the relationship between the two is also unclear. This study uses Meta-analysis to examine the relationship between information disclosure and M&As, as well as the impact of the moderating factors of analyst tracking, enterprise size, and measurement dimensions. Meta-analysis can integrate the scattered research results between information disclosure and M&As, which not only overcomes the limitations of the applicability of individual research conclusions, but also clarifies the reasons for the differences in previous studies. Secondly, existing studies focus on the impact of information disclosure on market value and resource allocation efficiency, that is, they mainly focus on the post-merger performance, and less attention has been paid on the impact of information disclosure on different stages in the process of M&As. This study distinguishes corporate mergers and reorganizations into pre-merger valuation efficiency and post-merger performance, thus enriching and developing the analysis framework of the influence of information disclosure on M&As in finance and information economics. Thirdly, this study reveals the impact of information disclosure on the efficiency of M&As, which is conducive to improving the effective allocation of resources in the control rights. The conclusions of this study provide empirical evidence and policy implication for protecting the interests of small and medium-sized investors, improving the regulatory mechanism of information disclosure of M&As in the new era, and promoting the healthy and sustainable development of the capital market. Future research can strengthen the analysis of the fields with less literature at present, such as the moderating effect of institutional environment, institutional investor ownership, political connections and other factors, and further explore the mechanism of information disclosure affecting M&As.