Abstract: Understanding the propagation of ultrahigh-speed plasma clouds in orbit is critical for studying their interactions with spacecraft materials. In this study, a drift-diffusion model was established using COMSOL’s rarefied gas transport module to simulate their behavior under varying neutral wind fields, orbital altitudes (500–1000 km), and initial plasma densities. The results indicate that at an initial velocity of 100 km·s^-1 and a propagation distance of 10 km, wind fields exert negligible influence on the plasma cloud’s density distribution at 0.1 s: the central density drops from 1.48×10²⁰ m^-3 (without wind) to 1.23×10²⁰ m^-3 (1500 m·s^-1 wind). Increasing orbital altitude accelerates propagation but lowers overall plasma density, while higher initial densities promote faster diffusion of He⁺/e^- clouds. These findings demonstrate the significant influence of environmental and intrinsic parameters on plasma cloud dynamics, providing theoretical guidance for the design of emission systems.