The invention relates to a side lifting/closing tarpaulin system for a flatbed trailer, the trailer having an elongated platform having front and rear ends, sides, a pair of bulkheads of similar construction extending upwardly from the platform at its front and rear ends, and a plurality of tarpaulin supporting beams extending laterally across the platform, and longitudinally along the platform. The system comprises a pair of pivoting arms, each arm supported by a corresponding bulkhead. The arms are pivotable, in corresponding fashion, with respect to a side of the platform, between an upper, open orientation and a lower, closed orientation. Each arm is provided with an elongated slot along a longitudinal axis of the arm. Each arm is mounted relative to the bulkhead such that the pivot sits within the slot in a manner that permits longitudinal movement of the arm relative to the pivot. There is further provided mechanical drive means to rotate the roller to roll or unroll the tarpaulin thus causing movement of the arms between the open and closed positions.