Influence of discharge from the State Amazon University (UEA) on the ichthyological diversity of the river Puyo, since Guevara & Ramos in 2018 stated that there is a 39% efficiency of the Wastewater Treatment Plant (PTAR) therefore several fish species are relegated from their habitat, for the determination of the study area the capture method was used by delimiting the discharge point of waste water as the starting area and the catches 1000 metres upwards, as well as 1000 metres downwards, by marking four sampling points in the above-mentioned areas, 30 minutes per sampling area were used using an atarraya to capture and photograph species within a 30-metre radius at the centre of the sampling points, 24 specimens from six families (Anostomidae, Cichlidae, Curimatidae, Characidae, Heptapteridae &Loricariidae), belonging to three orders (Characiformes, Perciformes & Siluriformes) where the predominant family is Loricariidae with 17 individuals, in the lower part is recorded a higher rate of orders versus the upper part in which two orders of the three obtained in total of the study are recorded.