Abstract Suicide is one of the leading causes of death from injury in Argentina, and there are few studies analyzing intra-urban geographic variations in developing countries. The scope of this study was to analyze the relationship between suicide and socioeconomic status and social fragmentation in small areas of the Autonomous City of Buenos Aires (CABA) during the 2011-2015 period. An ecological study was conducted using data on suicide records in the resident population of the CABA available at the National Ministry of Security. A multiple spatial regression was carried out to test the relationship between suicide and indicators of socioeconomic status and social fragmentation by area. The risk of suicide was positively associated with higher indices of social fragmentation, whereas it was not related to the indices of poverty. The results of this study support the hypothesis of social fragmentation as a factor positively associated with the increase of intra-urban suicide in cities of developing countries.