A rigorous analytical model for partially embedded large-diameter floating pile (PLFP) is devised based on a three-dimensional continuum pile and soil model. The analytical solutions to the dynamic response of PLFP are obtained using Fourier transformation and variable separation. Then, the accuracy of the obtained dynamic impedance and velocity is verified by comparing the derived values with existing solutions and the measured data of the experimental model. Finally, parameter analyses of dynamic impedance and velocity response are conducted. The results indicate the following. The use of a one-dimensional pile model to calculate the dynamic impedance of PLFP results in the overestimation of resonance amplitude and frequency. Defect detection is more difficult to implement in a partially embedded pile than in a fully embedded pile. In practice, the suitable position for a signal receiver installed on a pile head during low-strain pile integrity testing is 0.6r0.