Steady‐state space charge limited‐flow calculations have been carried out for an appliedB&Vthgr;magnetically insulated reflexing ion diode. Reflex ion energy spectra characteristic of a thin foil cathode and of a transparent mesh have been used. A one‐dimensional calculation shows higher ion current densities with a mesh cathode, and that the emission electron current density increases with the appliedB&Vthgr;magnetic field. The ion current density is calculated to increase slightly with radius.