Since the most widely used single-scattering phase function—Henyey-Greenstein scattering phase function (H-G scattering phase function) cannot reproduce the forward scattering and backscattering behavior well, a method based on the T-matrix scattering phase function was proposed to analyze and simulate the multiple scattering and echo signal of the pulse laser in the dust environments. The single-scattering properties of dust particles were calculated by the T-matrix method and a sample method was proposed to apply T-matrix scattering phase function to the Monte Carlo simulation with a random number. Furthermore, the theoretical model of the transmission and reception of a laser fuze in dust environments was built with the above sample method and semianalytic sensing geometric method of a photon. To verify the precision of the theoretical model, a dust environment laboratory was designed and built to evaluate the performance of laser fuzes in different dust environments. Therefore some experiments were completed to derive the echo amplitudes of a laser fuze in the dust environments with different dust concentrations and the results were compared with corresponding simulation results of H-G scattering phase function and T-matrix method. The simulation results show that echo powers are increased with the increase of dust concentrations and relative humidity. And the method based on T-matrix scattering phase function has a better consistency with the experiment and is more stable, especially in denser dust environments.