The　dynamic　surface　elasticity　of　the　solution　of　carboxymethylchitosan　(CMCH)　and　cetyltrimethylammonium　bromide　(C16TAB)　was　measured　as　a　function　of　the　surfactant　concentration　and　the　surface　age　by　the　oscillating　drop　method.　The　results　showed　that　the　surface　layer　of　the　CMCH/C16TAB　solution　transformed　from　loose　to　structured　with　the　increase　in　the　surfactant　concentration.　The　surface　elasticity　versus　the　surface　pressure　curve　during　the　adsorption　showed　different　features　at　different　surfactant　concentration　ranges,　which　was　connected　with　the　structural　transformation　of　the　surface　layer.　Our　results　show　that　the　measurement　of　dynamic　surface　dilational　properties　is　a　powerful　tool　for　studying　the　surface　kinetics,　which　is　helpful　for　dealing　non-equilibrium　systems　in　industry.