The　two-step　strategy　for　3D　reconstruction　of　complex　defects　was　updated　by　combining　the　magnetic　field　disturbance　(MFD)　with　magnetic　flux　leakage　(MFL)　measurement　methods.　Firstly,　the　plane-scanned　MFD　imaging　was　employed　to　achieve　high-accuracy　reconstruction　of　the　opening　outlines　of　complex　defects.　Secondly,　the　finite　element　simulation　model　of　the　defect　with　the　recognized　opening　outline　was　established　as　the　forward　model　for　depth　profile　inversion　with　the　particle　swarm　optimization　algorithm.　The　performances　of　the　conventional　MFL-based　and　updated　strategies　were　carefully　compared　through　finite　element　simulation.　The　results　proved　that　the　updated　method　combining　MFD　signals　with　MFL　signals　had　the　better　performance　in　accurate　3D　reconstruction　of　complex　defects　than　the　conventional　MFL-based　inversion　strategy,　displaying　smaller　errors　in　opening　outline,　peak　depth　and　the　profile.　Experimental　results　confirmed　that　the　updated　strategy　could　accurately　reconstruct　the　3D　shape　of　8-shaped　defect　and　rectangular　defect　with　rounded　corners.