Abstract: The dispersion characteristics of guided waves in a liquid-filled pipe embedded in the infinite medium is analyzed by using the wave propagation method. Based on the thin-shell vibration theory, the expressions of wavenumber in different transmission paths are obtained, and the vibration equation is studied by numerical method. The influences of the pipe parameters and the infinite medium on the dispersion characteristic of guided waves are analyzed. The results show that the pipe thickness-to-radius ratio, pipe wall thickness, infinite medium, and pipe wall material are closely related to the guided wave dispersion. The pipe thickness-to-radius ratio and the pipe wall material have great impacts on the dispersion characteristic of the fluid-dominated wave (s1 wave); the pipe wall thickness and the infinite medium influence the dispersion characteristic of the shell-compressed wave (s2 wave) significantly; and the simulation result confirm that the effect of the infinite medium on the dispersion characteristic of s2 wave is greater than that of s1 wave. This research has certain reference significance for the leakage detection of buried pipes.