Failure mode and effect analysis (FMEA) is one of the main approach for risk analysis and reliability engineering for under-development product or process analysis.This approach is based on the understanding of a multidisciplinary team about what is under analysis.That is, it is an approach that aggregate these different opinions about the failure modes.Its prioritization, considering the traditional approach, have been the concern of many research papers, witch are proposing different ways for combining the three indexes related to severity, occurrence and detectability (SOD).In the present work, one presents a probabilistic composition of preferences approach to establishes a priority order among the failure modes.The obtained results, from a simplified application case, shows the efficacy of the proposed method.