A non-intrusive method is used to measure surface tension of fuels and alkanes at high pressure. Capillary waves are generated on the liquid and a He-Ne laser beam is reflected at the free surface of the sample located in a pressured chamber. New results of surface tension are obtained versus pressure for diesel fuel, gasoline and n-heptane. Large variations with pressure under different atmospheres are shown. (C) 2004 Elsevier B.V. All rights reserved.