The use of different probability distributions as described by the Exponential, Pareto, Lognormal, Rayleigh, and Gama probability functions applied to estimation the time of the next large earthquake (Ms≥6.0) in different seismotectonic provinces of Iran. This prediction is based on the information about past earthquake occurrences in the given region and the basic assumption that future seismic activity will follow the pattern of past activity by maximizing the conditional probability of earthquake occurrence. The estimated recurrence times and the error of estimation for different distributions have been computed for different provinces. Results indicated Exponential model seem to be better than other models in prediction of occurrence time of the next earthquake in different seismotectonic provinces.