Objective To provide normal hemodynamic parameters of uterine spiral artery in the early pregnant women.Methods The hemodynamic parameters including peak systolic velocity(PSV),end diastolic velocity(EDV),resistance index(RI),pulsatility index(PI) and systolic/diastolic velocity ratio(S/D) of uterine spiral artery(SA) in 40 normal early pregnant women were studied by transvaginal color Doppler sonography.Result The flow mapping of SA in the early pregnant women was shown well,characterized by the higher EDV and the lower RI.Conclusion The changes of the SA hemodynamics are the most important features in the early pregnancy.