This book contains the key themes and insights from the presentations and posters presented at the Seventh International Workshop on the TianQin Science Mission (TQ7). TianQin, a Chinese space-based gravitational wave detection mission was initiated in 2014 and has since achieved several significant milestones, including the launch of the TianQin-1 experimental satellite. The construction of the TianQin-2 experimental satellites is currently underway, with a projected launch date set for 2026. These advancements are laying the groundwork for the TianQin-3 gravitational wave detection mission with the target launch around 2035. The book documents progress in the TianQin project ranging from scientific research to technological innovation and data analysis. Additionally, it provides updates on other gravitational wave detection missions, such as LISA, DECIGO, CPTA, and AliCPT. It serves as a valuable resource for professionals in the field and for anyone with a keen interest in the ongoing advancements in space science.