The　movement　of　the　three-phase　contact　line　with　chain　molecules　in　the　liquid　phase　displays　more　complex　mechanisms　compared　to　those　in　the　usual　liquid-liquid-solid　systems　and　even　to　the　gas-liquid-solid　systems　controlled　by　the　traditional　single-molecule　adsorption-desorption　mechanisms.　By　introducing　decane　molecules　with　chain　structures,　we　demonstrate　from　molecular　dynamics　insights　that　the　moving　mechanism　of　the　contact　line　in　a　water-decane-silica　system　is　totally　different　from　traditional　mechanisms.　Three　different　wettability-related　moving　mechanisms　including　＂Roll　up＂,　＂Piston＂　and　＂Shear＂　are　revealed　corresponding　to　the　hydrophilic,　intermediate　and　hydrophobic　three-phase　wettability,　respectively.　In　the　＂Roll　up＂　mechanism,　the　decane　molecules　are　rolled　up　by　the　competitively　adsorbed　water　molecules　and　then　move　forward　under　the　driving　force;　when　the　＂Piston＂　mechanism　happens,　the　decane　molecules　are　pushed　by　the　piston-like　water　phase　owing　to　the　comparable　adsorption　interactions　of　the　two　liquids　on　the　solid　surface;　in　the　＂Shear＂　mechanism,　the　contact　line　is　hard　to　drive　due　to　the　stronger　decane-silica　interactions　but　the　decane　molecules　far　away　from　the　solid　surface　will　move　forward.　Besides,　the　time-averaged　velocity　of　the　moving　contact　line　is　greatly　related　to　the　moving　mechanisms.　For　the　＂Roll　up＂　mechanism,　the　contact　line　velocity　increases　first　and　then　reaches　a　steady　value;　for　the　＂Piston＂　mechanism,　the　contact　line　velocity　has　a　maximum　value　at　the　start-up　stage　and　then　decreases　to　a　stable　value;　for　the　＂Shear＂　mechanism,　the　contact　line　velocity　fluctuates　around　zero　due　to　the　thermal　fluctuation　of　the　molecules.　Additionally,　the　mean　distance　from　Molecular　Kinetics　Theory　increases　with　decreasing　hydrophilicity　and　the　displacement　frequency　in　＂Roll　up＂　mechanism　is　2　orders　of　magnitude　higher　than　that　in　the　＂Piston＂　mechanism,　further　demonstrating　the　different　moving　mechanisms　from　a　quantitative　point　of　view.