A height self-adjustable walking aid includes two oppositely arranged U-shaped stands which are connected by a front stand. The two ends of each U-shaped stand are sleeved with two outer pipes respectively, and each outer pipe is mounted with a height adjusting apparatus and a control apparatus for height adjusting. The walking aid is adjustable in height according to the heights of users, so as to satisfy the requirement of allowing patients or elders with different heights to use a same equipment, thus providing great convenience for users. The heights of the two ends of each U-shaped stand could be adjustable respectively to generate a height difference between the front end and rear end of the walking end, thus enabling patients or elders to walk up and down the stairs with it.