Abstract: An invalid walker is disclosed. The walker comprises a pair of side frames each including two vertical legs joined by transverse members, an X-shaped frame comprising two cross-members pivotally connected to each other and joining the side frames at the front of the walker, with the upper ends of the cross-members being pivotally mounted on the upper ends of the legs and the lower ends of said cross-members being slidably mounted on the lower ends of the legs for permitting folding of the walker, a removable seat assembly which may be mounted on the side frames at the rear of the walker after entrance of the invalid into the walker, and means at the side frames at the front of the walker for maintaining the side frames apart during use.