An elliptical exercise machine includes a frame pivotally attached to a base, a pivotal coupling device pivotally coupling the base and the frame together, a retractable device having an outer tube pivotally coupled to the base, and an inner shaft slidably engaged in the outer tube and pivotally coupled to the pivotal coupling device for allowing the inner shaft to be moved into the outer tube or to be moved out of the outer tube when the frame is pivoted to the base, and a latching device for latching the inner shaft to the outer tube at any selected position and for allowing the elliptical exercise machine to be easily adjusted to different moving strokes and to be easily operated by the user.