Vaslui (Romanian pronunciation: [vasˈluj]) is a county (judeţ) of Romania, in the historical region Moldavia, with the seat at Vaslui.

In 2002, it had a population of 455,049 and the population density was 86/km².

This county has an area of 5,318 km².

The county lies on a plane, being bounded by the Prut River on the east and crossed in its centre by Bârlad River, a tributary of Siret River.

Vaslui County was heavily industrialised during the communist period and had large industrial complexes that went bankrupt during the 1990s. Today, the county's industry is mainly agricultural one, with other industries concentrated in the main urban areas.

County's main industries:

The main tourist destinations are the cities of Vaslui, Bârlad and Huşi. The Vaslui County Council, the county councils of the Moldovan Leova and Hînceşti districts, and the European Union (through the Phare program), have set up a program which seeks to promote tourism in these regions. The main tourist attractions of the Vaslui-Hînceşti-Leova touristic program are, among others, the medieval and early modern churches and monasteries, the Manuc Bei Hunting Palace and the Manuc - Mirzaian Manor Palace (similar to Manuc's Inn in Bucharest) in Hînceşti, as well as the region's natural riches.

Vaslui (Romanian pronunciation: [vasˈluj]), a city in eastern Romania, is the seat of Vaslui County, in the historical region of Moldavia.

The city administers five villages: Bahnari, Brodoc, Moara Grecilor, Rediu and Viişoara.

Archaeological surveys prove that the territory of Vaslui was inhabited since Neolithic. From the 14th century onwards, it developed the provincial town of Vaslui, with a population that varied strongly in the following centuries. The name of Vaslui appears first in a Polish document from 1375, referring to Koriat's son George. The name Vaslui was also mentioned in 1435, in connection with the accession of Prince Iliaş to the Moldavian throne. The town was burned to the ground in 1439 and 1440, when Tatars invaded Moldavia.

The peak of its importance was in the 15th century, when it was a second-rank capital of Moldavia, during the reign of Stephen the Great, with a population closer to that of the neighbour Iaşi. In 1475, Prince Stephen won his greatest battle against the Ottoman Empire in the Vaslui area. Once the Moldavian capital was moved from Suceava to Iaşi and the southern town of Bârlad became an administrative center of southern Moldavia, Vaslui declined for about three centuries to a local borough (târg).