Rates of self-harm among children and young people (CYP) have been on the rise, presenting major public health concerns in Australia and worldwide. However, there is a scarcity of evidence relating to self-harm among CYP from culturally and linguistically diverse (CALD) backgrounds.

To analyse the relationship between self-harm-related mental health presentations of CYP to emergency departments and CALD status in South Western Sydney (SWS), Australia.

We analysed electronic medical records of mental health-related emergency department presentations by CYP aged between 10 and up to 18 years in six public hospitals in the SWS region from January 2016 to March 2022. A multilevel logistic regression model was used on these data to assess the association between self-harm-related presentations and CALD status while adjusting for covariates and individual-level clustering.

Self-harm accounted for 2457 (31.5%) of the 7789 mental health-related emergency department presentations by CYP; CYP from a CALD background accounted for only 8% (n = 198) of the self-harm-related presentations. CYP from the lowest two most socioeconomic disadvantaged areas made 63% (n = 1544) of the total self-harm-related presentations. Findings of the regression models showed that CYP from a CALD background (compared with those from non-CALD backgrounds) had 19% lower odds of self-harm (adjusted odds ratio 0.81, 95% CI 0.66–0.99).

Findings of this study provide insights into the self-harm-related mental health presentations and other critical clinical features related to CYP from CALD backgrounds that could better inform health service planning and policy to manage self-harm presentations and mental health problems among CYP.