It　is　essential　to　understand　how　the　guided　waves　travel　in　benthal　pipes　in　order　to　monitor/inspect　their　health　statues.　In　this　paper,　the　propagation　characteristics　of　longitudinal　guided　waves　in　oil-filled　and　with　viscoelastic　coating　pipes　under　water　loading　have　been　investigated　by　a　global　matrix　method.　The　displacement　and　stress　distribution　in　pipes　have　been　numerically　calculated.　The　dispersion　curves　and　wave　structure　such　as　α　mode　and　L(0,　4)　mode　have　been　presented,　through　which　the　propagation　mechanism　for　the　longitudinal　guided　wave　traveling　in　the　pipe　is　demonstrated.　The　result　can　be　used　to　support　the　design　and　implementation　of　damage　detection　schemes　for　pipe-like　structures.