3D　bioprinting　is　a　potential　technology　for　fabricating　kidney　and　tracheal　grafts　since　the　matching　donors　is　insufficient　for　many　patients　on　demand.　However,　cell　damage　occurs　due　to　variety　factors　during　bioprinting　process　and　is　considered　as　a　possible　barrier　for　broad　applications　of　delicate　cells　3D　bioprinting.　Therefore,　Cell　viability　is　very　challenging　task　in　3D　bioprinting.　The　prime　objective　of　current　study　is　to　explore　effect　of　printing　frequency　on　cell　viability　during　printing　process　by　a　homemade　Pneumatic　Microdrop-on-Demand　(PMOD)　platform.　Thus　Human　Embryonic　Kidney　293　Cells　(HEK293Cs)　with　diameter　15~20　μm　and　Human　Bronchial　Epithelial　Cells　(HBECs)　with　diameter　50~70　μm　are　printed　to　different　sample　tubes　at　frequencies　of　10~70　Hz.　Non-ejected　cell　suspension　is　categorized　as　control　group.　Then　7-AAD　dye　and　flow　cytometry　method　are　utilized　to　evaluate　the　cell　viability.　It　is　found　that　the　relative　viabilities　of　HEK293Cs　and　HBECs　are　and　respectively.　Hence,　it　is　concluded　that　the　printing　frequency　has　no　significant　effect　on　cell　viability　and　PMOD　cell　printer　reaches　high　cell　viability　due　to　the　low　shear　stress　during　cell　printing　process　along　with　no　moving　component　in　the　bioink-filled　chamber.　©　2018　Association　for　Computing　Machinery.