Petroleum cokes are widely used in cement plants for energy generation. Because of their very low volatile content, the physicochemical processes occurring during their combustion should be mainly controlled by heterogeneous reactions. The reactivities of some petroleum cokes toward NO between 800 and 1000 degreesC have been characterized through experiments in an entrained flow reactor. These carbonaceous materials exhibit very high reactivities toward NO. Their capacity to reduce NO concentration in the surrounding gas is significant, so that this reaction can have a significant impact in terms of NO emissions resulting from their combustion. The influence of surface area and of the heavy metal content on surface reactivity was tested. As it was the case for carbon-oxygen reaction, the surface measured by mercury porosimetry seems to be a good parameter to calculate surface reaction rate. No correlation was found between calcium or iron content and NO-carbon reaction rate. As for the reaction of petroleum coke with oxygen, vanadium appears to have a catalytic effect on the reduction reaction of NO with carbon.