Sometimes the rock burst may occur in underground depth-mining. The conventional methods of predicting rock burst are briefly introduced in this paper. Based on the data of practical engineering and theoretical analysis, the conclusion has been reached that the rock burst occurs once each stress around the mining cave is up to or strong than the limit crush strength of the rock stratum around the mining cave. Base on this conclusion, the limit stress balanced method to predict rock burst and a new method to calculate each stress around the mining cave have been presented. The results of predicting rock burst by use of the new predicting method are in keeping with the practices.