Abstract: A liftable cover assembly for the bed of a truck having sidewalls and a tail gate. The cover assembly comprises a rigid cover panel sized to encompass the entire truck bed, plural support legs for the cover panel, a height establishing mechanism, and a locking mechanism. The support legs comprise a pair of generally U-shaped members pivotally mounted on the sidewalls and pivotally connected to the cover panel to enable the cover panel to be lifted from a lower or closed position, wherein it is horizontally disposed over the bed on the sidewalls and the tailgate, to a raised or open position, wherein it is disposed and held horizontally a predetermined distance above the sidewalls. The height establishing mechanism is adjustable to establish various predetermined distances that the cover may be disposed over the truck bed in the open position. The locking mechanism includes an actuatable handle and plural associated latches for locking the cover panel in the closed position.