Goudoumaria is located in the extreme south east of Niger and is part of ecological zones with strong climatic constraints especially rainfall. It is characterized by a strong spatio-temporal variability. The objective of this study is to identify the irregular nature of its distribution overtime that influences agropastoral activities. The results reveal rainfall interannual variability, its concentrations from June to September, a late start and early end and a downward trend. These results lead to a good understanding of rainfall evolution in the study area