A gull wing door assembly for an all-terrain utility vehicle (UTV) includes a hinge assembly configured to attach to an upper portion of the cage of the UTV, the hinge assembly having a rotational axis substantially parallel to the ground when attached to the cage, and a door configured to movably attach to the hinge assembly. The door may have a frame, one or more panels, a latch, and a lift-assist device such as a gas-strut.