ABSTRACT: The micromammal faunas from two European sections close to the Paleocene-Eocene boundary (PEb), Tremp in Spain and Dormaal in Belgium, share several species and paleoecological features in spite of their different chronological and paleobiogeographical situation: the Tremp faunas contain no immigrant taxa, while the Dormaal faunas post-dated the Mammal Dispersal Event. Both sections can be correlatedwith the Carbon Isotope Excursion (CIE) event, which lies several meters above the Tremp localities and could have begun sub-contemporaneously with the Dormaal Sand deposits. One of themost remarkable features of these faunas is the dominance in all the samples of dental micro-remains of the condylarth genus Paschatherium.Herewe study the features and distribution of Paschatherium species and discuss the significance of their acme in relation to the PEb and the Initial Eocene Thermal Maximum.