The invention provides an L-shaped composite material laminboard connecting structure with a flexible metal connector. The structure comprises foamed laminated composite material plates and metal connecting parts, wherein pre-buried metal plate parts of the metal connecting parts are embedded between laminated foams and composite material plates; composite material laminboards and the metal connecting parts are cured together by using an integral molding technique. Due to adoption of adjustable flexible connectors, the assembling stress is effectively reduced, and flexible assembling is achieved; the pre-buried metal plate parts are designed as a forked tail structure, so that the concentrated stress at the connecting parts of the metal plates and the composite material plates is effectively reduced; the connecting parts are of circular arc-shaped design, so that the bending strength is improved; due to a co-curing technique, composite material openings and the like are avoided, and the integrity of the composite material plates is ensured; a relatively large space is reserved in the metal connecting parts, so that convenience can be brought to pipeline laying and later maintenance. The structure is applicable to mechanical connection of composites material laminboards and other structures of large-size structures.