: To identify how Culturally and Linguistically Diverse (CALD) communities are defined in epidemiological research in Australia and provide a definition of CALD status that aids the consistency and interpretability of epidemiological studies. : Peer-reviewed literature from January 2015 to May 2020 was searched via four databases (Ovid Medline combined with PubMed, Embase, Emcare, and CINAHL) to identify quantitative studies of CALD people in Australia. : A total of 108 studies met the criteria for inclusion in the review. Country of birth was the most commonly used CALD definition ( = 33, 30.6%), with combinations of two or more components also frequently used ( = 31, 28.7%). No studies used all the components suggested as core to defining CALD status. including country of birth, languages other than English spoken at home, English proficiency, and indigenous status. : There was considerable inconsistency in how CALD status was defined. The review suggests that CALD status would best be defined as people born in non-English speaking countries, and/or who do not speak English at home. Additionally, indigenous peoples should be considered separately. This recommended definition will support the better identification of potential health disparity and needs in CALD and indigenous communities.