The exact placement of Peradectes and its relationships have been uncertain.
Some definitions of the group may be polyphyletic, and the extinct genus Thylacodon was thought by some to be synonymous with Peradectes; however, the two are now considered separate genera.

It is known to be a metatherian and further a member of the crown clade Marsupialia along with other extinct and extant groups due to distinct marsupial dentition and jaw anatomy.
Once thought to be a member of Didelphidae along with modern opossums, it is now classified within a separate family, Peradectidae, due in part to the predilambdodont, rather than true dilambdodont, upper molars.
Some classifications recognize a subfamily within Peradectidae, Peradectinae, which includes at least Peradectes, Thylacodon, and Nanodelphys.

Though no longer believed to be didelphids, the opossum-like Peradectes and its relatives in Peradectidae may represent a primitive step in the evolution of opossums.
A “peradectid or peradectid-like ancestor” may have given rise to didelphids in the Cretaceous.
The exact placement of Peradectes and its relationships have been uncertain. Some definitions of the group may be polyphyletic, and the extinct genus Thylacodon was thought by some to be synonymous with Peradectes; however, the two are now considered separate genera.
It is known to be a metatherian and further a member of the crown clade Marsupialia along with other extinct and extant groups due to distinct marsupial dentition and jaw anatomy. Once thought to be a member of Didelphidae along with modern opossums, it is now classified within a separate family, Peradectidae, due in part to the predilambdodont, rather than true dilambdodont, upper molars. Some classifications recognize a subfamily within Peradectidae, Peradectinae, which includes at least Peradectes, Thylacodon, and Nanodelphys.
Though no longer believed to be didelphids, the opossum-like Peradectes and its relatives in Peradectidae may represent a primitive step in the evolution of opossums. A “peradectid or peradectid-like ancestor” may have given rise to didelphids in the Cretaceous.
Peradectes