The invention discloses a gait phase detection apparatus with ankle joint angle self-rectification function, which comprises a shank fixing mechanism, a ankle joint angle control mechanism, a ankle joint angle measuring mechanism and a thenar pressure measuring footwear. The invention can control ankle joint motor rotation angle according to thenar pressure signal, regulate ankle joint angle for foot drop patient in weight reduction walking training, prevent the damage to foot due to the towing and impacting caused by foot drop, and improve the dorsiflexion ability of foot drop patient; a pressure sensor and an angle sensor collects thenar pressure signal and ankle joint angle signal timely, an upper computer performs fuzzy logic algorithm to realize to detect gait phase smoothly and submissively. patient with walking ability defects or normal person with some degree of gait deformity can wear the invention while walking, detect the gait phase information in walking, estimate gait recovery degree scientifically, and optimize gait training strategy.