An　embedded　electrocardiogram　(ECG)　recorder　based　on　ARM9　and　Linux　real-time　operating　system　(RTOS)　is　introduced　in　this　paper.　It　was　based　on　S3C2410X,　which　was　a　32-bit　low　power　micro-controller.　And　this　recorder　transplanted　Linux　RTOS.　We　developed　the　software　based　on　MiniGUI　which　was　a　lightweight　graphics　user　interface　support　system.　This　system　could　collect　the　ECG　signal,　calculate　the　heart　rate,　analyze　the　arrhythmia　and　send　the　alarm　by　GPRS　when　ECG　was　abnormal　in　real　time.　In　order　to　validate　the　veracity　of　system,　the　ECG　signals　generated　by　an　ECG　signal　generator,　which　was　a　multi-parameter　simulator　MPS450,　were　sampled　and　analyzed　by　this　recorder.　The　heart　rate　acquired　by　the　system　was　accordant　with　the　data　by　the　simulator.　The　recorder　could　send　alarm　information　automatically　through　GPRS　when　ECG　signal　was　abnormal　and　display　the　arrhythmia　on　the　main　interface.　Experiment　results　show　that　the　system　can　monitor　the　patient＇s　ECG　in　real　time,　detect　5　kinds　of　arrhythmias:　Tachycardia,　Bradycardia,　Arrhythmia,　Asystole　and　Dropped,　and　send　alarm　when　arrhythmias　happen.　So　the　wireless　monitoring　of　ECG　signals　can　be　implemented　by　this　system.