As rapid population aging has become a global challenge, the high prevalence of multimorbidity among older adults has also emerged as a pressing issue. Multimorbidity, characterized by the coexistence of multiple chronic conditions, can lead to a decline in older adults’ physical functioning and quality of life. Consequently, the challenges in long-term management of chronic diseases and related burdens may further exacerbate the vulnerability of older adults to depression. The objective of this study is to address the prevalence and impact of depression among older adults with multimorbidity and provide an updated summary of the intervention research on depression in this population. The findings would provide critical insights to inform healthcare professionals and government on developing tailored interventions to help older adults better manage multiple chronic conditions and enhance their well-being.