Highly　hydrophobic　surface　of　ZnO　crystal　substrate　is　prepared　easily　and　rapidly　by　KrF　excimer　laser　irradiation.　The　water　contact　angle　is　increased　from　70　degrees　to　approximately　120　degrees.　Through　the　XRD,　AFM,　XPS　measurements　and　the　Cassie-Baxter　model　analysis,　it　is　indicated　that　the　unique　micro-nano　fluctuant　surface　structure　induced　by　laser　irradiation　is　the　prominent　factor　to　the　great　increase　of　the　water　CA.　The　annealing　treatments　for　the　irradiated　sample　are　carried　out　both　in　oxygen　and　vacuum　atmosphere.　It　is　found　that　the　adsorption　of　oxygen　atoms　on　the　roughened　surface　could　make　the　CA　decrease　abruptly　at　the　first　beginning,　and　after　being　stored　at　ambient　atmosphere,　the　CA　would　reconvert　to　the　value　of　the　freshly　irradiated　sample　gradually.　It　probably　provides　a　convenient　method　for　rapid　conversion　of　the　wettability　through　excimer　laser　irradiation　and　post　annealing　treatment.　(C)　2012　Elsevier　B.　V.　All　rights　reserved.