A braking device for a wheelchair having at least one wheel and a frame having siderails adjacent the wheel is provided with a brake assembly surrounding the wheel for clamping and braking the motion of the wheel and with a connecting and mounting assembly connected to the brake assembly which mounts the brake assembly onto the siderail forward of the wheel and positions the brake assembly forward of the wheel parallel to and aligned with the axis of rotation of the wheel. Also provided is a brake actuating member connected to the mounting assembly which actuates the brake member. Still further, a locking member is provided adjacent the brake actuating member for locking the actuating member in position when the brake member is clamped to the wheel. The invention also discloses a structure for braking and clamping two wheels of a wheelchair with one brake actuating member.