Cognitive behavioural therapy for low self-esteem (LSE) has shown promise as a trans-diagnostic model for treating mental health difficulties in adults. To ascertain the potential value of this treatment approach in working with young people with internalizing disorders, we need to develop our understanding of LSE within these mental health conditions. The aim of this review is to explore (a) the co-occurrence of clinically significant anxiety/depression and LSE in young people (aged 18 years and younger), and (b) the association between LSE in childhood and adolescence and mental health difficulties in later adolescence and emerging adulthood.