Socio-environmental conflicts generate disputes between different stakeholders, who express different points of view about a subject that infringes human rights or provokes a severe environmental impact. At the same time, socio-environmental conflicts usually affect public opinion. The aim of this studio is to identify the use of information sources utilized by the Chilean media during the coverage of the crisis which affected Agrosuper and the population of Freirina (Chile), due to the pollution that generated the productive activity of that company (2012). Methodology. The content of several national and regional medias (newspapers, news portal, radio and television) was analyzed from May to December 2012. 302 pieces of news were analyzed. Results obtained reveal a remarkable weakness in the number and type of information sources used to cover this socio-environmental conflict. It's known that Chilean media generally use only one source, and as a result most of news aren't mentioned (53.3%). The most used sources belong to the institutional sources (67%).