Characterizations　of　debris　and　hole　diameter　in　CO2　laser　percussion　drilling　of　alumina　ceramic　(4.4　mm　thick)　under　various　processing　parameters　were　investigated.　The　main　energetic　parameters,　including　laser　peak　power,　pulse　frequency,　pulse　duty　cycle,　and　piercing　time,　were　selected　as　independent　variables　to　be　studied.　The　process　qualities　were　evaluated　in　terms　of　the　characteristics　of　debris,　hole　entrance　and　exit　diameter.　Based　on　the　experimental　results,　it　was　found　that　laser　peak　power　affected　vaporization　rate;　pulse　duty　cycle　influenced　melt　rate;　pulse　frequency　affected　valid　heating　efficiency　in　base　material;　and　piercing　time　influenced　drilled　depth　before　beam　break-through.　On　the　process　qualities　(debris,　entrance　and　exit　diameter),　laser　peak　power　and　duty　cycle　had　significant　effects,　pulse　frequency　had　a　lower　effect,　while　piercing　time　had　the　lowest　effect.　Comparatively,　peak　power　had　a　higher　effect　than　duty　cycle　on　the　formation　of　debris.　Furthermore,　higher　pulse　frequency　could　induce　more　symmetrical　and　smaller　debris　especially　when　the　laser　incidence　angle　was　not　zero　and　hence　the　melt　ejected　along　a　particular　direction.