He studied painting and sculpting at the Athens School of Fine Arts with professors such as Nikephoros Lytras and Broutos.
Roumpos drew mostly portraits and busts, such the ones of architect Aristotelis Zahos, poet and playwright Polyvios Dimitrakopoulos, Rigas Feraios, Athanasios Diakos and others.
A marble bust that he made of the poet Lorentzos Mavilis is placed at the square of the same name in Athens.
The same bust exists in three additional copies: in Corfu, Ioannina and at the Offices of Greek Writers.
Petros Roumpos' work includes funerary monuments, such as the one of the family of Georgios Athenogenous (1910), with a seated winged figure, at the First Cemetery of Athens, as well as the Monument dedicated to the high priests in Tripoli, with engraved details of the acts of the Arcadians during the Greek War of Independence.