Abstract: Thermal management of high-speed optical module interconnect systems is crucial for achieving cloud computing and 5G networks, but there is currently no relevant research content. The current heat dissipation of high-speed interconnect systems for optical modules mainly relies on the use of heat sinks and fans. With the widespread deployment of high-speed optical modules above 400Gbit/s, the heat dissipation problem of optical module interconnect systems has also received more attention and faces greater challenges. This paper takes the QSFP-DD high-speed optical module interconnection system as the research object, establishes a thermal model of the QSFP-DD high-speed optical module interconnection system, and studies the effects of ventilation grill free area ratio (FAR), fin height and quantity of heatsink on the heat transfer performance of the QSFP-DD high-speed interconnection system through numerical simulations.