A portable workbench is provided for holding a work piece, and includes a bench top, foldable legs, and a plurality of horizontal and vertical holes adapted to receive a pipe clamp for clamping the work piece to the bench top. The bench top is a torsion box with an internal grid so that the workbench is lightweight, yet strong and stable. The legs include two-piece crossbraces which are quickly and easily connected and disconnected via male and female ends and a securing pin.