Italy with an annual production of 20 million tons is the leading producer of electric arc furnace (EAF) steel in Europe. The geographical distribution of EAF steel producers is concentrated in Lombardy, therefore the macro sector of metallurgical industry is related to that of vulcanized rubber as it is located in the same geographical area. The aim of this work is to assess the influence of EAF slag as filler for nitrile butadiene rubber (NBR) in order to promote an alternative use of EAF slag by preventing its disposal. The processability characteristics of filled NBR are determined by the rheometric curves; the first results show that the presence of slag in NBR accelerates the crosslinking kinetics. The mechanical characterization, consisting of hardness and compression test and compression set, shows a stiffening of the material that could affect positively the gasket behavior in sealing system assembled both in load or in displacement control.