Polistes sulcifer is a species of paper wasp in the genus Polistes that is found in Italy and Croatia. It is one of only three known Polistes obligate social parasites, sometimes referred to as "cuckoo paper wasps", and its host is the congeneric species Polistes dominula. Because it is an obligate social parasite, this species has lost the ability to build nests, and relies on the host workers to raise its brood. P. sulcifer females use brute force, followed by chemical mimicry in order to successfully usurp a host nest and take over as the queen.