The Astronist Church, also known as The Church of Astronism, is an organisation considering itself as a denomination of Astronism, yet diverges from mainstream Astronic thought, especially from the Millettarian Tradition, by self-identifying as a religion rather than a philosophy.

Essentially, those whom are part of the Astronist Church consider Astronism to be a religion rather than an organised philosophy, the latter designation of which has been affirmably upheld by The Institution of The Philosophy of Millettism, the organisation holding proprietorship over Astronism, since The Philosophy's founding. The reason for the controversy of the Astronist Church stems from the clear designation of Astronism as an organised philosophy as distinct from a religion by Cometan in the founding treatise of the Omnidoxy.

Nevertheless, the Astronist Church is considered a denomination of Astronism and a branch of the Millettarian philosophical tradition and does continue to be in a state of vicinality with The Institution.