In this work, nanocomposites constituted of FeCo alloy nanoparticles dispersed on a highly porous silica aerogel have been designed as catalysts for low temperature Fischer-Tropsch synthesis. The catalysts were characterized by XRD, TEM, N-2 physisorption and SEM analysis. A high catalytic activity with CO conversions up to 95 % has been obtained, with enhanced selectivity for the C-2-C-4 hydrocarbons.