Aiming to solve the problem of corrosion and high cost of the conductive fillers, the powders with the properties of anti-oxidation, corrosion resistance and thermal stability should be developed. A new modification technology, rare earth gaseous penetration, was applied to enhance the conductivity of maifanite in this paper, and the mechanism for improving the conductivity of maifanite effectively was speculated in detail for the variations of the composition, structure and morphology between the original and Er-penetration maifanite powders. The results of the resistivity show that Er-penetration can really improve the conductivity of maifanite powders. When the penetration temperature is 500 ℃, the resistivity of maifanite surprisingly declines to 93.2 Ω·m. Moreover, XRD and XPS patterns display that the cations in maifanite are substituted by Er3+ successfully, resulting in the production of electrons in the system, which is the key reason to heighten the conductivity of maifanite. Most importantly, Erpenetration maifanite, whose price is really low, can replace the expensive conductive powders and be used in the electronic industry to decrease the cost of the electronic devices.