The Siluriformes conservation state was quantified by means of the SUMIN index, composed by the sum of 12 outstanding variables for the species survival and/or conservation. An arranged list of the thirty -three Siluriformes species from the Ramsar Site was obtained based on a gradient of conservation necessity. The species were defined as Vulnerable of Maximum Priority: Pseudoplatystoma corruscans, P. f. fasciatum, Luciopimeloduspati and Hemisorubimplatyrhinchos; species Vulnerables of Special Attention: Oxydoras kneri, Ageneiosus valenciennesi, Sorubim lima, Platydoras costatus, Pterodoras granulosus, Sturisoma robustum, Trachydoras paraguayensis and Ageneiosus brevifilis. The remaining species, were qualified as Not Threatened: Corydoras paleatus, Pimelodus ornatus, Loricariichthys anus, Pimelodus albicans, P. maculatus, Hypostomus commersoni, Loricariichthys platymetopon, Pimelodus brevis, Paraloricaria vetula, Parastegophilus maculatus, Trachelyopterus striatulus, T. cf. galeatus, Bergiaria westermanni, Pimelodella laticeps, Liposarcus anisitsi, Otocinclus vittatus, Loricaria simillima, Parapimelodus valenciennis, Pimelodellagracilis, Auchenipterus osteomystax and Hoplosternum littorale.