In　this　research,　the　tribological　characteristics　of　PEEK　filled　with　short　carbon　fiber/PTFE/Graphite　sliding　against　AISI630　stainless　steel　under　water　lubrication　were　investigated.　The　friction　experiments　were　conducted　on　MCF-10　ring-on-ring　test　rig.　Based　on　SEM　analysis　of　worn　surfaces,　an　attempt　was　made　to　approach　the　tribological　mechanism　of　friction　pairs.　The　results　showed　that　the　matching　materials　achieved　the　best　tribological　performance　at　velocity　of　1　m/s　and　load　of　1.66　MPa.　When　load　applied　on　the　specimens　was　increased　to　2.49-3.32　MPa,　cracks　and　delamination　wear　occurred　in　the　surface　of　PEEK.　The　effect　of　sliding　velocity　on　triobological　performance　of　matching　materials　was　complicated.　At　higher　sliding　velocity,　hydrodynamic　lubrication　was　easier　to　form.　However,　the　rapid　rising　temperature　with　the　increase　of　sliding　velocity　had　adverse　effect　on　water　lubrication　film.　Under　load　of　1.66　MPa　and　sliding　velocity　of　1.5-2　m/s,　adhesive　wear　was　the　dominant　factor　in　the　sliding　process.　The　matching　materials　performed　higher　friction　coefficient　and　wear　rates　under　insufficient　water　lubrication　than　that　under　circulating　water　lubrication.　It　is　attributed　to　that　the　friction　heat　accumulated　gradually.　The　research　results　will　lay　the　foundation　for　the　materials　screening　of　key　friction　pairs　in　the　water　hydraulic　components.