Аннотация:A flood flow regime is typical of rivers over most parts of the world. The particular feature of this regime consists of random annual fluctuations in the number of flood peaks, the dates of their passage, and the height and form of separate peaks. One of the ways of improving methods for hydrological computations is to increase the efficiency of use of the given hydrologic data in taking into account the particular feature of a flood flow regime. For this purpose a stochastic model of fluctuations in runoff during a flood period is presented. It includes a stochastic model of the hydrograph — for a flood season and a stochastic model of the annual fluctuations of its characteristics