The Ensemble Prediction System (EPS) in principle can be called the Probabilistic Prediction System (PPS) of which its ultimate goal is to provide the full probabilistic forecast for all variables. Compared to the beginning of EPS era in 1992 that just considered the uncertainties existed in the initial conditions, one of the most significant progresses made on ensemble techniques during the past few years, is that the model uncertainties have been taken into account, and then is the development of the multi model and multi analysis ensembles.Some problems existed in the operational EPS such as the generation of initial perturbations, multi model ensembles, the application of ensemble products and its verifications are described, and the outlook of this perspective technique is exhibited.