To investigate ANT1 and NF-κB expression in inclusion body myositis (IBM) muscle and to verify their possible roles in the pathogenesis of the disease, we collected muscle samples from five patients with IBM, polimyositis (PM) and controls. p65 form of NF-κB was analyzed using immunocytochemistry, Western blot and EMSA. Western blot of ANT1 was performed and confirmed by gene expression study. Mann-Whitney test was used for groups comparisons. NF-κB (p65) was found over-expressed both with western blot and EMSA, either in IBM or PM patients versus controls (p < 0.01). Expression of ANT1 were lower in IBM samples versus both PM and controls (p < 0.01). ANT1 reduction and NF-κB over-expression in IBM muscle could explain the lack of apoptosis in such disease. Normal ANT1 expression in PM could be related to the scarcity of mitochondrial abnormalities in the disease, but it could also suggest that these two conditions diverge in activating different anti-apoptotic pathways.