The effects of waveform and frequency on proliferation of human lung adenocarcinoma cell line A549 were studied by FX-4000 strain unit . The results showed that cellular proliferation index (PI) reduced significantly in squarewave group when compared with the control after A549 cells were subjected to collagen I 0-25% elongation at frequency 20 cycles/min, 40 cycles/min and 60 cycles/min for 2h. The PI showed no distinct difference in trianglewave group. The PI increased in heartwave group. These data indicate that A549 cells do respond to physiological strain in vitro. The effects of squarewave and 60 cycles/min tension may be optimal for inhibiting the proliferation of A549 cells. To select appropriate waveform and frequency will be of paramount importance to inhibiting proliferation of A549 cells.