The origin, the name and the history of the two villages on both sides of the Prut River: Petreşti, Iaşi, Romania, and Petreşti, Ungheni district, Republic of Moldova, were the same: old and Romanian. The spli took place in the fatal year 1812, with the annexation of Moldova between the Prut and the Dniester to the Russian Empire. The numerous attempts to define their past have been hit by the poverty of the written, blurring sources, but also by the confusion generated by the large number of localities with the Petreşti toponym, existing in the Moldavian geographic area in the feudal age. Moreover, for the Petreşti settlement on the left bank of the river, in the Soviet years, it was attempted to impose a history with a strong Russian touch, and the presence of Țar Peter I being mentioned here in 1711 as a reason for the establishement of the settlement. By analyzing critically the written documents, the author of the article reveals the unity of the destiny of these two settlements, showing that the first documentary attestation of Petreşti village on the Prut River, from the former county of Iaşi, is the year1645. The name of the settlement is probably from a founder of Peter - a founder of a social group - people on the estate of a landowner, inhabitants of the village of the first founder. As a result of the annexation of 1812, part of the inhabitants of the settlement remained to live on the old countryside of the village, on the right of the river, while others chose to live under the Russians, laying on the side of the estate on the left of the Prut, a new one with the same name - Petresti.