In　the　course　of　investigating　traffic　safety　threat　the　direct　diagnosis　couldn＇t　concentrate　on　convergences　of　crashes　within　the　limited　section,　so　the　boundary　of　a　segment　with　abnormal　crashes　may　not　be　captured　accurately.　Continuous　pattern　recognition　is　a　new　screening　method　for　traffic　safety　diagnosis.　The　segments　with　potential　problems　of　traffic　safety　could　be　identified　by　successive　movement　and　scanning　every　interval.　Steps　and　main　points　of　analysis　about　the　technology　were　given.　Quantitative　calculation　of　the　abnormal　extent　of　crash　was　studied.　The　technology　is　easy　to　operate　with　computer　programming　because　of　repeated　calculation.　It　could　judge　the　positions　of　traffic　safety　threats　correctly,　then　countermeasures　could　be　made　and　traffic　safety　of　the　road　would　be　improved.