Arc　fault　has　been　one　of　the　main　factors　of　the　fire　disaster.　An　effective　and　reliable　detection　and　analysis　method　for　arc　fault　is　the　key　to　research　arc　fault　detection　device　(AFDD).　In　order　to　research　arc　fault,　a　system　that　featured　with　friendly　man-machine　interface　and　flexible　operation　is　built　for　arc　fault.　The　system　hardware　is　based　on　a　computer,　data　acquisition　card,　voltage　and　current　sensor,　arc　fault　simulation　apparatus.　The　system　software　platform　is　designed　by　the　multithreading　technology　to　realize　arc　voltage　and　current　real　time　acquisition,　waveform　real　time　display,　storage　and　analysis.　Real　time　control　between　the　software　platform　and　the　system　hardware　is　realized　through　serial　communication.　Periodic　difference　algorithm　is　applied　to　extract　the　periodicity　singularity　point　to　identify　the　arc　fault　s.　In　addition,　the　system　possesses　of　abundant　functions　such　as　automatic　forming　test　report,　historical　data　inquiry,　etc.　Results　show　that　the　system　is　able　to　simulate　arc　fault,　and　arc　fault　detection　and　identification.