In order to increase petroleum oil recovery, the wettability of the interface between flooding aqueous solution and oil reservior plays an important role. A surfactant dissolved in the flooding solution can be adsorbed on the reservior surface and then the wettability of the interface can be changed. For the purpose of mimic oil recovery, a cationic gemini surfactant, ethanediyl-alpha,beta-bis( cetyldimethylammonium bromide) ( 16- 2- 16), was synthesized and characterized. The dynamic surface and interface tensions have been measured using pendant drop method at the air-water surface and dodecane-water interface, and experimental curve is close to orientation model and interaction model of surface equations of state. Compared with conventional cationic surfactants, cetyldimethylammonium bromide ( CTAB), 16- 2- 16 has very low cmc value (1.8 x 10(-5) mol/L to 1.0 x 10(-3) mol/L). The most hydrophilic condition between the surfactant aqueous solution and the silica powder surface appears near the cmc for both 16- 2- 16 and CTAB. The best mimic oil recovery is also reached around the cmc for the two surfactants, but the efficiency for the former (68%) is higher than the one for the latter (63%). (C) 2005 Springer Science + Business Media, Inc.