Abstract In this paper, the authors explored the effects of processing variables, including carbon nanotube (CNT) concentration, assembly pressure, and processing temperature, on electrical conductivity of CNT-included electrically conductive adhesives (ECAs). The main effects of these variables were analyzed under specific range for each variable. Response surface methodology was used to investigate the cross-effects of these variables on ECA conductivity. By fitting the experimental data to the response function, minimum bulk resistivity of 1.5×10 −4 Ω cm was obtained at the optimum settings of processing variables (CNT concentration 2%, processing temperature 199 °C, pressure 6000 psi).