Dexmedetomidine (Dex) is a highly selective alpha2‑adrenergic receptor (α2‑AR) agonist with unique sedative, analgesic, and anti‑sympathetic effect and widely used in clinical anesthesia and intensive care unit. Recent studies have found that Dex has the capacity to modulate negative emotions, improve sleep disturbances, and protect the nervous system, and is less addictive, indicating its potential to treat psychiatric disorders. This review focuses on the application of Dex in anxiety, depression, and sleep disorders, explore its potential value in the field of psychiatry, and provide new ideas for the clinical treatment of psychiatric disorders.