Background: Zonal flows are the electrostatic modes with structures of toroidal symmetry and poloidal symmetry

which play an important role in restraining turbulences. In the process of turbulence suppression

the poloidal rotation widely exists in tokamak plasmas. Purpose: In this study

the effects of the poloidal rotation on zonal flows in tokamak plasmas are concluded. Methods: With the dispersion relation derived by using ideal MHD model with the adiabatic approximation

the frequencies of zonal flows are deduced. Results: Firstly

the frequency of the geodesic acoustic mode (GAM) increases with respect to the poloidal Mach number when adiabatic coefficient is 5/3. Secondly

the frequency of the sound wave (SW) increases with respect to the poloidal Mach number when adiabatic coefficient is 5/3. Thirdly

the frequency of GAM with γ=1 is different from that when γ=5/3. The fourth

the frequency of SW with γ=1 is different from that when γ=5/3. The last

the ratio between the cos and sin components of density perturbation for GAM is a very small value in the poloidally rotating plasma. Conclusion: It is shown that the frequencies of the zonal flows with the adiabatic approximation

increase with respect to the poloidal Mach number

but differ in numerical value of the frequencies of the zonal flows with the isothermal approximation. In contrast to the pure standing wave form in static plasmas

the density perturbations consist of a standing wave superimposed with a small amplitude traveling wave in the poloidally rotating plasma. Abstract