In a spark plug, a base material contains 50 mass % or more of Ni, 8 mass % or more and 40 mass % or less of Cr, 0.01 mass % or more and 2 mass % or less of Si, 0.01 mass % or more and 2 mass % or less of Al, 0.01 mass % or more and 2 mass % or less of Mn, 0.01 mass % or more and 0.1 mass % or less of C, and 0.001 mass % or more and 5 mass % or less of Fe. A discharge member contains at least Pt of a P group (Pt, Rh, Ir, and Ru) and Ni. The atomic concentration K of the P group of the discharge member, the atomic concentration L of the P group of the base material, the atomic concentration M of Ni of the discharge member, and the atomic concentration N of Ni of the base material satisfy (K+L)/(M+N)≤1.14.