Traditional　cryptography　based　authenticated　Diffie-Hellman　key　exchange　protocols　expose　the　problems　of　efficiency　and　privacy　since　signature-then-encryption　is　heavy　to　wireless　communication　special　for　flexible　dynamic　deployment,　i.e.,　wireless　mesh　networks,　wireless　sensor　networks,　mobile　ad　hoc　networks,　etc.,　in　computational　cost　and　communicational　overhead　and　traditional　digital　signature　allows　anyone　to　verify　its　validity　using　the　corresponding　public　key.　In　this　paper,　we　propose　a　signcryption　based　light　weight　key　exchange　protocol　named　SLWKE　which　can　provide　resistance　to　traditional　attacks,　i.e.,　eavesdropping,　deducing,　replaying,　interleaving,　forging　and　repudiating,　and　unknown　key-share　attack　and　save　computational　cost　by　three　modular　calculations,　i.e.,　one　modular　inversion,　one　modular　addition　and　one　modular　multiplicative,　included　in　a　signature　s　and　communicational　overhead　by　secure　length　of　vertical　bar　q　vertical　bar　in　comparison　to　signcryption　based　direct　key　exchange　using　a　time-stamp　protocol　termed　DKEUTS.　(C)　2012　Published　by　Elsevier　B.V.　Selection　and/or　peer-review　under　responsibility　of　Garry　Lee