【Abstract】 Background Acute lung injury is a common clinical devastating symptom ,which has been thought to be a tough problem in critical medicine for its high morbidity and mortality. Objective This review summarized the possible protective mechanisms of electro-acupuncture in acute lung injury. Content Some mechanisms seem to be involved in the protective process of ALI, including the balance between oxidation/anti-oxidation system, pro-inflammation/anti-inflammation system, neuroendocrine system, vasodilatation/vasoconstriction system, and so on. Trend The pathogenesis of ALI are complicated ,endogenous protective system could be mobilized by electro-acupuncture to protect lung functions, and there may exit associations or cross-talk among those protective mechanisms.