Chronic pain and sleep disorders are prevalent clinical issues that often coexist, significantly impacting patients’ health and imposing a substantial healthcare burden on society. Clinical studies suggest that chronic pain can lead to sleep disturbances, while sleep disorders may exacerbate chronic pain or trigger new pain, creating a vicious cycle. The underlying mechanisms involve neurotransmitter imbalances, immune dysregulation, oxidative stress, and neural circuitry dysfunction. This review summarizes the bidirectional interactions and mechanisms between chronic pain and sleep disorders, aiming to provide new therapeutic strategies for the prevention and treatment of comorbid sleep disorders and chronic pain.