The Irminio (Sicilian: Iriminiu; Italian: Irminio; Latin: Hirminius) is a 55-kilometre long river located in south-eastern Sicily, southern Italy. It is the most important of the rivers of the province of Ragusa.
The river springs from Monte Lauro, the main peak of the Hyblaean Mountains, which form the main part of the mountainous southeast of Sicily and runs across the province from north-east to south-west before flowing into the Mediterranean Sea 2.5 kilometres east of Marina di Ragusa. Its main affluences are the streams Cava Volpe, Ciaramite, Mastratto, and near Ragusa Ibla the streams San Leonardo and Santa Domenica.
