Abstract: OBJECTIVE To explore the effects of p70S6K1 in colorectal cancer (CRC) and its association with bufalin. METHODS In this study， the change of p70S6K1 expression in CRC tissues was detected by immunohistochemistry， and the correlation between p70S6K1 and CRC patient outcomes was evaluated. Furthermore， the effects of PF-4708671 on cell growth， cellular senescence， cell cycle and cell migration of CRC were determined by MTT assay， β-galactosidase staining， cell cycle staining and wound-healing assay， respectively. In addition， the effects of bufalin on growth rate of CRC cells and p70S6K1 expression were assessed. RESULTS The expression of p70S6K1 was increased in CRC samples compared to normal controls， which was associated with poor prognosis. PF-4708671 treatment reduced cell growth rate， induced cellular senescence， arrested cell cycle and attenuated cell migration ability by inhibiting p70S6K1 expression. Bufalin could restrain cell growth distinctly by decreasing downregulate p70S6K1 expression. CONCLUSION These findings suggest that p70S6K1 may be a new target of bufalin， and can act as a potential therapeutic target for CRC treatment.