The　warning　system　has　become　the　urgent　demand　of　commercial　competition,　and　the　representation　of　all　kinds　of　the　monitored　indexes　of　the　warning　system　is　the　hard　core.　In　this　paper,　the　semantic　network　is　applied　to　define　the　domain　ontology　of　the　system,　and　Dublin　Core　is　introduced　to　annotate　knowledge.　Furthermore,　the　formalization　based　on　OWL+　Dublin　Core　is　provided.　Predicate　logic　is　combined　with　production　KR,　as　a　method　to　describe　the　reasoning　rule　in　the　knowledge　base.　We　also　take　the　warning　system　of　technical　barriers　to　trade　for　example　to　explain　its　application.