Electrode and method of manufacturing the same of the spark plug, as well as the method of manufacturing the spark plug and spark plug

According to the present invention, at least one of a center electrode or a ground electrode is produced by mixing a matrix metal with carbon so that the carbon content of the resultant mixture is adjusted to 80 vol.% or less; subjecting the mixture to powder compacting or sintering, to thereby form a core; placing the core in a cup formed of nickel or a metal containing nickel as a main component; and subjecting the cup to cold working. The thus-produced electrode exhibits favorable thermal conductivity and good heat dissipation, by virtue of the small difference in thermal expansion coefficient between the core and an outer shell. Therefore, a spark plug including the electrode exhibits excellent durability.