3DOR is the dedicated workshop series for methods, applications and benchmark-based evaluation of 3D object retrieval, classification, and similarity-based object processing. In 2023, the 3DOR will be organized as a Symposium with the ambition to attract a larger number of participants. The symposium also includes the 2023 edition of the 3D Shape Retrieval Challenge (SHREC), keynotes, project presentations, and a social and networking event. Accepted full papers will be published in Computers & Graphics Journal (Elsevier), and accepted short papers will appear in the Eurographics Digital Library.