A collapsible camper top for pick-up trucks which is characterized by multiple nesting and telescoping sections which are sealed by bottom and top reverse curved, rubber seal members and are adapted to extend and cove the bed of a pick-up truck. The number of nesting sections which are used is dictated by the length of the pick-up truck bed and the sections are nested and retracted in accordion-like fashion inside a fixed section to expose the bed of the pick-up truck for hauling purposes. In a preferred embodiment the nesting sections are mounted on rollers which operate in plate slots provided in roller plates carried by the side rails of the pick-up truck. In another preferred embodiment the nesting sections are extended and retracted by means of a chain drive system which is operated by an electric motor or is capable of hand-operation by a crank. A rear window slides inside tracks provided in the end collapsible section to open the rear end of the collapsible camper top and is deployed outwardly and downwardly of the tracks to close the end section of the collapsible camper top.