In this article, EH01 field components are evaluated in a cylindrical waveguide filled with plasma in the presence of external static magnetic field applied along the direction of the mode propagation. The electron acceleration inside the plasma-filled cylindrical waveguide is investigated numerically for a single-electron model. It is found that the electron acceleration is very sensitive to the initial phase of mode-field components, external static magnetic field, plasma density, point of injection of the electron, and microwave power density. The maximum amplitude of the EH01 mode’s field components is approximately 100 times greater than the vacuum-waveguide case for operating microwave frequency f = 7.64 GHz, plasma density n0 = 1.08×1017 m−3, initial phase angle ϕ0 = 60°, and microwave power ∼ 14 MW in a cylindrical waveguide with a radius of 2.1 cm. An electron with 100 keV gets 27 MeV energy gain in 2.5 cm along the waveguide length in the presence of external power ∼ 14 MW with a microwave frequency of 7.64 GHz. The electron trajectory is also analyzed under the effects of magnetic field when the electron is injected in the waveguide at r = R/2.