Cities with a high content of light pollution are illuminated 24 hours a day, this generates light pollution. Light pollution does not only the vision of people, but also affect the animals of the place, who find themselves in the need to migrate to other areas, darker where they can perform their daily activities, with greater insecurity for them. This study aimed to measure the level of knowledge of the light pollution, data collected from 384 people living in Lima, Peru was examined. Findings suggested that in general, only 4% of people interviewed have high knowledge of what light pollution is, while 20% had medium knowledge and 76% of people interviewed had low knowledge of the subject.