It　is　the　hypothesis　of　imbalance　vibration　monitoring　and　dynamic　balance　to　separate　the　imbalance　vibration　signal　accurately.　The　compositive　method　of　accurate　imbalance　vibration　signal　separation　was　given　based　on　some　methods,　such　as　signal　forecasting　and　extension　of　time　series　model,　EMD　and　correlation　analysis　etc.　The　principle　and　procedure　of　the　method　were　introduced　in　detail　based　on　radial　vibration　signal　analysis　of　the　motor　spindle.　In　order　to　test　the　validity　of　the　method,　further　unbalance　experimentation　and　signal　separation　were　carried　out.　©　2010　IEEE.