In　this　study,　the　fabrication　of　microfluidic　chip　ontaining　a　row　of　198　micropillars　was　described.　The　geometric　deformation　of　micropillars　in　icrofluidic　chip　on　the　PI　and　PMMA　substrates　was　aused　by　cumulative　heat　during　laser　ablation.　nalysis　of　the　cumulative　heat　effect　of　PI　polyimide)　and　PMMA　was　done　(polymethyl　ethacrylate)　when　ablated　using　a　KrF　excimer　laser　or　microfluidic.　We　researched　the　variation　of　icropillars＇　geometric　deformation　on　the　different　luence　and　the　number　of　laser　pulses　according　to　xperimental　observations.　The　number　of　laser　pulses　enerates　a　greater　geometric　deformation　in　PMMA　than　in　PI.　The　diameter　of　the　top　of　micropillars　increase　is　attributed　to　a　smaller　thermal　expansion　coefficient　of　PI　that　enables　a　smaller　melted　volume　o　form.　In　connection　with　PI,　The　relation　between　the　laser　pulses　and　the　top　and　bottom　diameter　of　the　icropillars　has　been　got.　The　cause　has　been　analyzed.