Brazil faces a complex scenario of natural hazards, essentially as a direct result of its size, diversity and both its natural and social heterogeneity. In 2011, massive landslides were triggered by extreme rainfall that caused the so-called “Mega disaster” in the mountainous region of Rio de Janeiro. This paper describes the development of a social vulnerability index at the census tract level using SoVI method. It also examines the potential value of the Social Vulnerability Index to explain the impact of the 2011 landslides on population of Nova Friburgo municipality. Principal Component analysis reveals that six factors explain 73.6% of the data variance. Spatial pattern analysis suggests that about 84% of the area is classified with moderate level of social vulnerability. The highest social vulnerability values are concentrated in areas where population density is high and the main economic activities are developed. The resulting knowledge provides to local community, government and civil organizations with a basis to comprehend the geography and drivers of social vulnerability, which can be leveraged to achieve an effective preparation and response to face future natural hazards and also to promote disaster-resilient societies