To　solve　the　problem　that　the　relationship　between　various　types　of　damage　and　different　influencing　factors　of　bridge　under　earthquake　is　complicated　and　difficult　to　find,　the　damage　situation　of　the　bridge　was　analyzed　combined　with　bridge　pier　type,　structure　type,　bearing　type,　plane　line　shape,　foundation　type,　intersection　angle,　fault　distance,　and　peak　ground　acceleration.　The　conditional　attribute　of　bridge　damage　were　reduced　by　using　the　dominance　relation-based　rough　set　approach.　The　minimum　sets　of　association　rules　of　374　bridges　in　Wenchuan　earthquake　were　extracted.　Another　20　bridges　were　selected　for　testing.　Results　were　compared　with　indiscernibility　relational　rough　set　theory　and　classification　and　regression　tree　algorithm.　Results　show　that　for　the　evaluation　system　of　post-earthquake　bridge　damage　state,　compared　to　the　traditional　generation　rule　based　on　indiscernibility　relation　rough　set　theory　and　classification　and　regression　tree　algorithm,　the　dominance　relation-based　rough　set　approach　is　more　accurate,　and　can　be　used　in　the　future　research　of　bridge　damage　discrimination　studies　and　rule　extraction.　©　2023　Beijing　University　of　Technology.　All　rights　reserved.