The present invention relates to an electric crutch with a length locking mechanism, capable of preventing the electric crutch from accidentally changing length through an internal driving and locking mechanism. The mechanism includes a transmission base, a driving disc, and at least one locking post. The transmission base is configured to connect to a DC motor inside the electric crutch, and convexly arranged with a plurality of pushing blocks on the bottom part. The driving disc is arranged with a plurality of displacement grooves in circumferential directions, wherein one end of the displacement groove is concavely arranged with a locking groove for installing the locking post, the pushing block can extend into the displacement groove to drive the driving disc to rotate through pushing the locking post, which in turn changes the length of the electric crutch. When the driving disc is loosened due to an external force, since the locking post is abutted against by the inner wall of the electric crutch, the driving disc is locked in an unrotatable state, thereby locking the length of the electric crutch.本發明係一種具長度鎖定機制之電動拐杖，係透過內部之一驅動及鎖定機構，防止電動拐杖意外改變其長度，該機構包括傳動座、驅動盤及至少一鎖制柱，該傳動座能與電動拐杖內之一直流馬達相連接，且底部凸設有複數個推動塊；驅動盤沿圓周向設有複數個位移槽，該位移槽之一端凹設有鎖制槽，以供安裝鎖制柱，推動塊能伸入位移槽中，以透過推抵鎖制柱，帶動驅動盤旋轉，進而改變電動拐杖之長度；在驅動盤因外力影響鬆動時，由於鎖制柱會被電動拐杖之內壁所牴觸，故能將驅動盤鎖制於無法轉動之狀態，以鎖定電動拐杖之長度。
