In our modern society, everyone argues constantly about the mass media information work. In that context, it’s imperative to know how much the different society ‘actors’ trust information enterprises. Moreover, it’s necessary to make a difference between credibility and media uses, as well as between media uses and truth or falsehood coming under information. This article is based on a recent investigation made by the Media Observatory of the Social Communications Faculty in La Sabana University. The inquest reveals the contradictions that exist into colombian society: a hight rating media doesn’t have always the expected credibility, while some low rating media are leaded by famous and reliable journalists. In conclusion, it looks like media credibility specially depends on how much citizens participation ways they have, which means that they clearly help people to build society and people’s life.