Abstract : The aim of this PhD work was the development of electrically and thermally conductive adhesives for space applications. It begins with the manufacturing by CCVD of double-walled carbon nanotubes (DWCNTs). These DWCNTs or commercial MWCNTs are dispersed by solvent route with micrometric silver flakes (µAg) in an epoxy matrix (EP). A characterization of resulting composites (EP + µAg + DWCNTs and EP + µAg + MWCNTs) follows: study of the microstructure, the electrical and thermal conductivities and the mechanical properties. Two types of reliability tests show lastly stable electrical properties over the time and higher mechanical properties than commercial thermally conductive adhesives currently in use in space industry.