 Born in Râmnicu Vâlcea, Marinescu graduated from the Bucharest Politehnica Institute's Faculty of Aerospace engineering in 1976, and subsequently worked as an engineer for Avioane SA and Aviation Institute branch in Craiova.He entered politics in 1992, as a member of the PDL (known then as Democratic Party, PD), when he was elected a member of the Craiova City Council.Marinescu was elected Vice-president of the PD local section in Craiova (1994) and Dolj County (1997), and, in 2001, Secretary for Dolj County and Oltenia.