A stroller comprising: a front leg (31, 32); a middle leg located rearward of the front leg (31, 32); a rear leg located rearward of the middle leg; a front-wheel holding mechanism provided on the front leg (31, 32), the front-wheel holding mechanism being configured to rotatably and turnably hold a front wheel; a middle-wheel holding mechanism provided on the middle leg, the middle-wheel holding mechanism being configured to rotatably and unturnably hold a middle wheel; a rear-wheel holding mechanism provided on the rear leg, the rear-wheel holding mechanism being configured to rotatably and turnably hold a rear wheel; and a handle; wherein the stroller is capable of letting babies ride thereon in such a manner that the babies are seated in a back to front direction; characterized in that the stroller further comprises: a fourth link element pivotably joined, at a rear portion thereof, to the handle, and pivotably joined to an upper portion of the rear leg; a first link element pivotably joined, at a rear portion thereof, to the handle, and pivotably joined, at a front portion thereof, to the front leg (31, 32); a second link element pivotably joined to a front portion of the fourth link element, and pivotably joined to an intermediate portion of the first link element; a third link element pivotably joined, at a rear portion thereof, to the second link element, and pivotably joined to an upper portion of the front leg (31, 32) and an upper portion of the middle leg; a fifth link element pivotably joined to the second link element and the middle leg, respectively; and a sixth link element pivotably joined to the handle and the rear leg, respectively. a front leg (31, 32); a middle leg located rearward of the front leg (31, 32); a rear leg located rearward of the middle leg; a front-wheel holding mechanism provided on the front leg (31, 32), the front-wheel holding mechanism being configured to rotatably and turnably hold a front wheel; a middle-wheel holding mechanism provided on the middle leg, the middle-wheel holding mechanism being configured to rotatably and unturnably hold a middle wheel; a rear-wheel holding mechanism provided on the rear leg, the rear-wheel holding mechanism being configured to rotatably and turnably hold a rear wheel; and a handle; wherein the stroller is capable of letting babies ride thereon in such a manner that the babies are seated in a back to front direction; characterized in that the stroller further comprises: a fourth link element pivotably joined, at a rear portion thereof, to the handle, and pivotably joined to an upper portion of the rear leg; a first link element pivotably joined, at a rear portion thereof, to the handle, and pivotably joined, at a front portion thereof, to the front leg (31, 32); a second link element pivotably joined to a front portion of the fourth link element, and pivotably joined to an intermediate portion of the first link element; a third link element pivotably joined, at a rear portion thereof, to the second link element, and pivotably joined to an upper portion of the front leg (31, 32) and an upper portion of the middle leg; a fifth link element pivotably joined to the second link element and the middle leg, respectively; and a sixth link element pivotably joined to the handle and the rear leg, respectively. a fourth link element pivotably joined, at a rear portion thereof, to the handle, and pivotably joined to an upper portion of the rear leg; a first link element pivotably joined, at a rear portion thereof, to the handle, and pivotably joined, at a front portion thereof, to the front leg (31, 32); a second link element pivotably joined to a front portion of the fourth link element, and pivotably joined to an intermediate portion of the first link element; a third link element pivotably joined, at a rear portion thereof, to the second link element, and pivotably joined to an upper portion of the front leg (31, 32) and an upper portion of the middle leg; a fifth link element pivotably joined to the second link element and the middle leg, respectively; and a sixth link element pivotably joined to the handle and the rear leg, respectively.