Based on the basic principles and technical characteristics of satellite communication, it expounds its advantages in wide coverage, low transmission delay, large capacity, and high reliability. An in-depth analysis of the basic characteristics, key technologies, and development trends of 5G and 6G networks is made, emphasizing the key role of satellite communications in achieving seamless global coverage, supporting high-speed data transmission and low-latency communications. Especially in 5G networks, satellite communication is utilized through high-throughput satellite (HTS) and low earth orbit (LEO) satellite networks; for 6G networks, satellite communication is expected to adopt more advanced technology solutions such as emerging frequency bands and integrated artificial intelligence to support a wider range of application scenarios and higher data transmission requirements.