Abstract ‘Lived mental health experience’ (LMHE) describes direct impact of a mental health problem or being a mental health carer. The phenomenon of LMHE among Trainee Clinical Psychologists (TCP) is rarely investigated despite encountering challenges throughout training. Conducting research which quantifies prevalence of mental health problems among TCPs may help training courses, organisations, leaders and researchers observe relevance and necessity to drive biopsychosocial initiatives, effective interventions, and combat stigma. The current study aimed to estimate point, period, and lifetime prevalence of LMHE among TCPs. UK-based TCPs ( N=301) completed an online survey. Results found 39.9% identified as a mental health carer at some point in life (current for 21.2%; historical for 32.8%) with 38.5% acquiring mental health carer responsibilities before training, and 6.6% since training commenced. Additionally, 44.9% and 45.2% respectively reported experiencing a diagnosed or undiagnosed mental health problem at some point in life (current for 55.8%; historical for 63.6%). Moreover, 86.4% reported a mental health problem prior to training, and 11.2% since training started. TCPs are likely to experience a mental health problem or identify as a mental health carer at some point in their life either before or during their doctoral training. The dissemination of prevalence rates to DClinPsy course staff and employing trusts may be useful in their practice in terms of developing resources and promoting adaptations to support TCPS with LMHE. This may facilitate normalisation of LMHE within this population and combat stigma. Key words: Trainee Clinical Psychologist, Clinical Psychology, Lived Experience, Lived Mental Health Experience, Prevalence