A folding ladder with an armrest, has two front legs, two rear legs, two shaft sleeves and at least a footboard, two shaft sleeves are respectively sleeved on the top portion of the two front legs, the top portion of the two rear legs are respectively rotatably pivoted to the two shaft sleeves; further comprising an armrest, the armrest comprises two movable bars and a link bar, two movable bars are respectively connected to the two front legs in stretchable way, the link bar is connected between the two movable bars; the shaft sleeve is disposed with an adjustable switch to control the movable bar to stretch out and draw back. The adjustable switch has a handle, a position pin disposed at one end of the handle and an elastic element disposed at the other end of the handle.