The characteristics of one‐dimensional electron diode with low‐pressure argon scattering gas are analyzed by a Monte Carlo method. Experimentally determined differential elastic scattering cross sections, extra‐polated to zero energy, are employed. Current‐voltage characteristics are compared with those obtained from a hard‐sphere collision model. Negative resistance is found for low emission current densities and low pressure as a result of the Ramsauer cross section. The randomization of energy between velocity components is found to be quite large for accelerating potentials and pressure‐electrode separation values as low as ½ Torr·cm. The energy dependence of total cross section has a more pronounced effect on the current‐voltage curves than nonisotropic scattering.