A sport-wheeled chassis is provided for connecting to a mobility device, which comprises a suspension set up under the bottom of the mobility device, a steering pivotally connected to the suspension, a controller connected to the suspension and steering electrically, tires which are pivotally connected to the steering and disposed under the steering, and a steering shaft of the steering which coincides axially with the steering shaft of the tire so that the controller can operate the turning direction of the tire and the height of the suspension through the suspension and the steering. The chassis is not only with a simple structure, but also with a suspension to control the height of the chassis off the ground, so that the chassis can maintain stability in any rugged environment, and, with its attached wheels, the chassis can move to desired places fast and accurately.