Animism led to the worship of various gods in ancient China for rewards e.g. sheltering and good harvest while star worship had a special place among numerous national rituals. Stars were usually worshipped for their intimacy to daily life, for instance, the Masters of Wind and of Rain and the Star of Dragon were related to the yield forecasting of agriculture, the Northern Dipper was believed to have an authority over people’s life, and Canopus gave signals to the life span of the emperor and the people. The worship of Canopus was established as an independent ritual, but the content and ceremony, even the subject of ritual, underwent modifications in different period, which is a uncommon phenomenon in national rituals that emphases on the continuation of tradition. Through an investigation of the national worship of Canopus between Qin to Song dynasties, I will show how the above changes are related to the development of astronomical knowledge and contemporary politics.