The propagation and attenuation characteristics of electromagnetic waves through a waveguide filled with moving isotropic lossy homogeneous (TEmnmodes), as well as inhomogeneous (TEm0modes) plasma for the appropriate modes, have been theoretically studied. The expressions for the propagation and attenuation constants for TE and TM modes are found to be the same and dependent on waveguide dimension, plasma parameters, and drift velocity. The propagation characteristics near the waveguide walls are seen to be similar to the free‐space waveguide. For special cases, the effect of the inhomogeneity of the plasma medium has also been discussed. The power flow and field components existing in waveguides are also discussed in brief.