The importance of electrode paste is emphasized in the recent big trend in the industry. However, a widely used electrode paste is based on silver. Silver is used in many fields due to its high stability, but it has the disadvantage of being expensive. Accordingly, copper, which has high conductivity and is inexpensive, is attracting attention as a metal for electrode paste to replace silver. However, copper has not been widely applied in the industry because of its easily oxidizing properties. To overcome these shortcomings of copper, a strategy to prevent oxidation of copper using polyaniline was established in this study, and a Polyaniline/Copper (PANI/Cu) nanocomposite with good atmospheric stability was synthesized. The synthesized Polyaniline/Copper (PANI/Cu) nanocomposite has a conductivity of 10^3 S/cm to 10^4 S/cm and will be a new material to replace copper with high atmospheric stability.