Abstract: Ferritic heat-resisting cast steel, which intends to highten the applicability for use of the exhaust manifold of a vehicle engine without losing oxidation resistance, machinability and structural stability, containing, on a weight basis, 0.05 to 0.5% C, 1.0 to 2.0% Si, less than 0.6% Mn, less than 0.04% P, less than 0.04% S, less than 0.5% Ni, 10 to 20% Cr, 0.1 to 1.0% V, 0.5 to 1.0% Nb, 0.08 to 0.50% Mo, less than 0.01% W and 0.01 to 0.2% Ce, the balance of its composition being iron. Alternatively, it may contain 0.1 to 1.5% Mn and 0.01 to 0.2% S, and may further contain 0.01 to 0.2% Te and/or 0.01 to 0.3% Al. Further, it may contain 0.1 to 5.0% Co and/or 0.1 to 5.0% Ti. The cast steel is annealed at a temperature of 850.degree. C. to 1000.degree. C. for one to five hours.