Two　types　of　titanium　surfaces　covering　with　TiO2　micro/nanostructures　were　fabricated　by　femtosecond　laser　structuring　followed　by　NaOH　hydrothermal　or　H2O2　oxidation　treatments.　After　exposure　to　air,　the　former　surface　maintained　hydrophilic　for　10　days　and　had　a　minimum　contact　angle　less　than　20　degrees　even　after　50　days,　while　the　latter　surface　changed　to　superhydrophobic　with　a　contact　angle　more　than　150　degrees　after　50　days.　Detailed　analysis　in　terms　of　morphology,　phase　transformation　and　surface　chemistry　indicated　that　the　changes　of　wettability　behavior　were　associated　with　the　adsorption　of　organic　compounds　from　the　surrounding　atmosphere.　The　surface　prepared　by　laser　and　H2O2　oxidation　not　only　had　a　stronger　adsorption　ability　than　the　surface　prepared　by　laser　and　NaOH　treatment,　but　also　exhibited　a　relative　higher　hydrophobic　hydrocarbon　tail　in　the　absorbed　compounds,　which　resulted　different　wettability　evolution　trend　for　the　two　types　of　titanium　surfaces.