Abstract: Foldable cart for shopping having a rigid base for reinforcement of the bag bottom. Two frames carry the wheels on which the bag leans in the unfolded position during use. The frames allow the wheels to be folded beneath the rigid base. Bag supporting frameworks can be extended and folded by parallel sliding in order to allow extension for pulling the cart or folding to a bag of reduced size for hand transport. One of the frameworks is attached to the upper zone of the bag, pulling the latter for its extension or folding. The other framework has, close to an articulation axle at the rigid base of the bag, a piece provided with one or two lugs which pass through slots formed in the housing for articulation of the frameworks and the wheel frames and for automatic extension of the wheels.