Abstract: This study investigates the heat transfer characteristics of a penetrating liquid cooling module, conducts an in-depth analysis of its thermal resistance composition based on specific cases, and establishes a chip junction temperature prediction model. By constructing two-dimensional thermal resistance simplified models for both liquid cooling modules and traditional modules, the heat transfer paths of the modules are analyzed, revealing the unique features of the heat transfer paths in the liquid cooling module. Based on the theory of equivalent thermal resistance, a thermal resistance network model for the module is developed, and combined with the thermal resistance 45° calculation method, a chip junction temperature prediction model is established. Through thermal simulation verification, the reliability of the model is confirmed, with prediction errors below 1%. Compared to traditional modules, the penetrating liquid cooling module demonstrates significant advantages in shortening the heat transfer path and reducing the number of interfaces. Further analysis indicates that the thermal resistance of the thermal insulation pad and convective heat transfer are the key factors affecting the heat dissipation performance of the liquid cooling module. By selecting interface materials with better thermal conductivity and optimizing the internal flow channel structure of the module, the heat transfer performance of the penetrating liquid cooling module can be effectively improved.