This paper examines the relationship between crime, perception of security, land use and type of housing unit in two typical residential boroughs in Porto Allegre, namely, Menino Deus and Rio Branco. Data related to occurrence of street robbery and residential burglary was collected in the Public Security Department of State of Rio Grande do Sul, for a period of tem months and through questionnaires applied to a sample of 123 residents in Menino Deus Borough and 86 in Rio Branco Borough. This method also allowed the gathering of information concerning residents’ satisfaction levels with security. Land use identified as residential or non residential as the types of housing units, if houses or flats, were obtained through the Municipal Department of Planning. Data was registered in ArcGIS, allowing the generation of maps and the consequent visualization, for example, of the spatial distribution of the two type of crimes, as well as in the SPSS/PC software, where data was statistically analyzed. Results reveal, for example, the impact made by land use and type of housing units on occurrence of crime and in the perception of security, allowing a better understanding of the relationship between street robbery and residential burglary and some physical characteristics of the urban space.