Depressive disorder is a kind of affective disorder， and its pathogenesis involves multiple factors. Inflammation may be one of the pathophysiological mechanisms underlying depressive disorder. Currently， studies have shown changes in interleukin-6 （IL-6） in patients with depressive disorder. This paper summarizes the pathogenesis of IL-6 and depressive disorder， as well as the role of IL-6 in different clinical treatment methods， and explores the role of IL-6 in the occurrence and prognosis of depression， providing reference for further elucidating the activity patterns and mechanisms of IL-6 in the pathogenesis of depressive disorder.