In　order　to　make　the　actual　flow　velocity　of　micro-channels　be　consistent　with　the　theoretical　value　and　make　sure　that　the　amplification　process　and　the　steps　of　PCR　chip　are　completed　exactly,　it　is　needed　to　do　real-time　measurement　and　flow　control　of　the　actural　work　fluid　flow　condition.　The　fluorescence　signal　value　of　the　micro-channel　filled　with　the　strong　active　fluorescence　PCR　reagent　was　about　4　times　as　great　as　that　of　the　empty　micro-channel　and　10　times　as　great　as　that　of　the　micro-channel　filled　with　the　negative　fluorescence　PCR　reagent　in　the　39　cycled　micro-channels　of　biological　PCR　micro-fluidic　chip.　Based　on　the　above　fact,　a　proposal　was　made　that　the　real-time　fluorescence　detection　micro-sensor　should　be　set　up　on　the　chip　to　sense　the　information　feedback,　so　the　condition　of　the　velocity　of　flow　in　the　microchannel　could　be　feed　backed　in　time　and　the　velocity　of　flow　could　be　controlled.