Abstract: This paper explores the data from more than twenty rainfall recording gages to develop Intensity Duration Frequency (IDF) relationships in the north-eastern part of Algeria. Using non parametric tests, a primary screening of rainfall data has been carried out to check that the annual time series variates are random, homogeneous and doen not contain any outlier. Severe storm intensities are calculated for various recurrence intervals using the General Extreme Value (GEV) probability distribution law. A three parameter geometric model that relates intensity to duration and return period, with highly significant correlation, is developed for each rainfall station. Such models, that describe the rainfall characteristics are useful tools in water structures design and rainfall-runoff modelling. They readily give the expected rainfall intensity of a given duration of storm having desired frequency of occurrence.