Abstract: Using the simple parameters obtained by phase analysis in gated myocardial perfusion imaging (GMPI) to evaluate the left ventricular mechanical dyssynchrony has the advantages of simplicity and repeatability, while the parameters can be affected by many factors. GMPI phase analysis has wide potentials, including cardiac resynchronization therapy, early diagnosis of several cardiac diseases, helping clinical decision-making and predicting the clinical outcome of diseases. This review briefly introduces GMPI phase analysis and its progress in clinical application.