Pigs can be orally infected with Salmonella sp. that rapidly (in 30 min) invade the tonsils and subsequently, through lymphatic spread, reach the mandibular lymph nodes. These infected lymphatic tissues may constitute an important reservoir of Salmonella sp. playing a crucial role as a source of contamination during the slaughter process, promoting the introduction of Salmonella into the food chain.The main objective of this work was the study of Salmonella sp. occurrence in mandibular lymph nodes and in tonsils of slaughtered pigs, to define the level of association between these two lymphatic tissues concerning Salmonella infection. For this purpose, RFLP-PFGE was used to identify the clonal relationships between Salmonella sp. strains isolated from the mandibular lymph nodes and from the tonsils. The study revealed the presence of Salmonella in 12.9% of the mandibular lymph nodes and in 9.9% of the tonsils, from which 70% were associated to positive mandibular lymph nodes. This association emphasizes the importance of these lymphatic tissues as Salmonella sp. carriers, and alerts to the fact that particular and additional measures, in the context of the new European Regulation, should be implemented during the slaughter process in order to reduce the level of Salmonella sp. contamination.