The rivers account as vital arteries of most plains in Iran. This type of water resources depends on dominant
climate types of different regions, represents different reaction versus environmental stresses, especially
hydrological drought. The hydrological and climatological droughts have priority and coming next
together. Therefore, investigated relationship between hydrological droughts of Babolrood river in Babol
plain were compared with climatological drought synoptic station affecting the discharge of Babolrood
river. In this research, stochastic and probability models (Markov chain), Run theory, moving average and
SPI index were used, so that hydrological and climatological drought and wet year were simulated at 10
years later. Results represent that Ghaemshahr synoptic station will have the most droughts frequency
occurred in study period. Using Markov chain showed that the most static probable in normal state belongs
to Babolrood river with value of 0.633. The occurrence of drought and wet years in Babolrood river are
more under effect of Ghaemshahr station. This relation was established by using paired sample T test with
significance level of (p<0.05) and correlation equal to 0.576.