The objective of the this study was to analyse the socioenvironmental, economic and sanitary aspects of an informal settlement located in the neighborhood of Parque São Luiz, in the municipality of Guarulhos, state of São Paulo. It is an anthropized area on the right bank of the Cocho Velho stream, part of the Baquirivu Guaçu river, a tributary of the Tietê river. In order to better understand human impact on the local environment, we carried out a geographical characterization of the site using satellite images, a historical survey of the occupation through in loco visits, literature data, and an evaluation of the socio-environmental, economic and sanitary indicators. To this end, residents of 34 homes were formally interviewed. The number of dwellers varied from one to four per household. The mean age of the interviewees was 33.4 years old (SD = 13.75; min = 12; max = 63). The results revealed lack of sanitary sewage in all residences, inadequate ventilation due to the absence of windows in 23.5% of them, and 29% of the residents stated that their garbage is dumped directly into the river and agglomeration of people in 32% of households (more than four inhabitants), presence of synanthropic animals inside all houses, among other socio