PURPOSE: To obtain the titled yarn having high strength and high modulus of elasticity and excellent electrical conductivity, by coagulating dope of para- orientated aramid by a specific method and uniformly adding copper sulfide to the prepared yarn by a special method.

CONSTITUTION: First optically anisotropic dope consisting of para-orientated aramid having ≥3.5 intrinsic viscosity ηinh and a sulfuric acid solvent is prepared. Then, the dope is extruded through an orifice to air once, coagulated and tension is released from the coagulated yarn in coagulation period and/or initial period of washing wherein the amount of remaining sulfuric acid solvent is ≥5wt.% based on the dried yarn. Successively, the yarn having ≥80wt.% water content is brought into contact with a solution containing a copper compound under release of tension and the copper compound is dispersed into the yarn. Further the yarn is brought into contact with a solution containing sulfurizing agent and dried at ≥120°C to give the aimed yarn uniformly containing ≥0.1wt.% based on yarn weight of copper sulfide in the interior of the yarn and ≥1.41g/cm3 density.