Adjustable elbow crutch with a main single piece that acts as leg-arm on which a handle and cuff are fixed, for which the handle includes an opening through which the leg-arm passes, said opening constituting an anchor for the handle on the leg-arm, where furthermore the leg-arm is made out of composite material, with an oval cross-section, and the leg-arm disposes of an initial lower segment that is vertical and which is followed in its upper part by a curved segment which defines a support angle. In this way a crutch is obtained that is light, easy to handle, easy and safe to adjust, which covers a continuous range of adjustments and which covers the largest number of possible user categories.