The Astronomical Journal (often abbreviated AJ in scientific papers and references) is a peer-reviewed monthly scientific journal owned by the American Astronomical Society (AAS) and currently published by IOP Publishing.

Until 2008, the journal was published by the University of Chicago Press on behalf of the AAS.

The other two publications of the society, the Astrophysical Journal and its supplement series, followed in January 2009.

In 1941, editor Benjamin Boss arranged to transfer responsibility for the journal to the AAS.

On January 1, 2022, the AAS Journals, including AJ, transitioned to Gold open access model, with all new papers released under a Creative Commons Attribution license and access restrictions and subscription charges removed from previously published papers.