Aspergillus: is a genus of filamentous and cosmopolitan fungi that includes important species for medical mycology, food, basic research and agro-industry areas. Aspergillus section Nigri are efficient producers of hydrolytic enzymes such as cellulases that are employed in the cellulose conversion. Hence, the search of new cellulolytic isolates and their correct identification is important for carrying out safe biotechnological processes. This study aimed to characterise the cellulolytic potential of Aspergillus sp. LBM 134, isolated from the Paranaense rainforest (Argentina) and to identify the isolate through a polyphasic approach. The fungus was identified as Aspergillus niger and its cellulolytic potential was evaluated by using Congo red technique and fluorescence plate assays for carboxymethyl cellulase, β-glucosidase and cellobiohydrolase, respectively. All three cellulase activities were positive; this bio-prospective positioned A. niger LBM 134 as a promising alternative for industries that require organisms capable of carrying out cellulosic biomass processing.