This study's objective was to measure the vulnerability index of families in the municipality of Pasto, Colombia. In a sample of 270 families of all socioeconomic strata (239 urban and 31 rural), a confidential survey was conducted using the vulnerability index, consisting of five dimensions: demographic, social, economic, environmental, and geography, forecasting, and prevention. The families in strata 1 and 2 and the houses in the center, west, northwest, and northeast of the urban area showed high vulnerability, even higher than those in rural areas. Fifty percent of the families showed low vulnerability and 42% medium vulnerability. The poorest families were the most vulnerable, but poor families were also vulnerable in the municipality of Pasto.