The Chironomidae fauna of ten large European rivers (Rhine, Elbe, Oder, Danube, Loire, Pripjat, Po, Maas, Garonne and Rhône) were investigated by analysing their ecological traits (longitudinal zonation pattern, saprobiological affinities, feeding types) using one-dimensional and multivariate methods. The results confirm the geomorphological differentiation of these rivers in two main types, i.e. gravel-type and sand-type rivers. The analyses of the Chironomidae traits also showed that transition zones separate the two main types of rivers.