With the advocacy of the strategy of "bringing in and going out" in recent years, cross-border mergers and acquisitions in the game industry have become a major way for the development of the game industry. Chinese Internet company-Tencent is one of the largest leaders in the whole China's game industry. In recent years, Tencent has made many attempts to acquire overseas game companies to help them with the market competition. Among them the most important one must be Tencent's acquisition of the UK's sumo group in 2017.This paper uses the case study method to study the performance development and overall revenue changes of Chinese Internet company Tencent after its acquisition of UK-based sumo group game studio in 2021. This paper analyzes the motivation of Tencent's acquisition of sumo group, performance impact analysis, development prospects and other aspects, and finally draws a conclusion. At the same time, it puts forward suggestions for Tencent's future development strategy.