Abstract: To study the impact of printing process on the cell viability, two types of human living cells, human peripheral blood mononuclear cells (hPBMCs, 10-15 μm in diameter) and human bronchial epithelial cells (hBECs, 50-70 μm in diameter), were printed at several jetting frequencies from 10 Hz to 70 Hz. The printing device was a home-made pneumatic drop-on-demand generator with a diameter nozzle, and producing micro-droplet with size of 180-200 μm. Non-ejected cell suspension was taken as control group, while in experimental groups about 6 000 drops of cell suspension were delivered to sample tube containing phosphate buffered saline (PBS) for each jetting frequency. Then 7-AAD dye and cytometry methodwere utilized to evaluate the cell viability. The relative viabilities of hPBMCs and hBECs are 0.991±0.009 and 0.996±0.014, respectively. The experimental analysis shows that the jetting frequency has no significant effect on cell viability, and the pneumatic printing device can reach high cell viability that may result from the low viscosity of printing cell-load suspension and low shear stress during the cell printing process. The pneumatic printing can be successfully applied in the fields of bioprinting.