The invention discloses a telescopic and foldable steel structure mobile garage, comprising a first supporting rod, a second supporting rod, a third supporting rod, a fourth supporting rod, a fifth supporting rod, a sixth supporting rod, an X-shaped hinge frame and a controller; a first hinge lug and a first sliding block are fixed at the lower end of each of the first supporting rod, the second supporting rod, the third supporting rod, the fourth supporting rod, the fifth supporting rod and the sixth supporting rod; a second hinge lug is fixed on a first sliding block; the lower end of the X-shaped hinge frame is hinged with the first hinge lugs; the upper end of the X-shaped hinge frame is hinged with the second hinge lug; first supporting plates are fixed to the left end of the first supporting rod and the left end of the fourth supporting rod correspondingly, a first hinge base, a second hinge base and a third hinge base are fixed to each first supporting plate from left to right correspondingly, and first lifting rods, second lifting rods and third lifting rods are hinged to the first hinge bases, the second hinge bases and the third hinge bases respectively. The garage has the beneficial effects of being simple in structure and high in practicability.