Oină (Romanian pronunciation: [ˈoj.nə]) is a Romanian traditional sport, similar in many ways to baseball and lapta.

Oină was first mentioned during the rule of Vlaicu Vodă in 1364, when it spread all across Wallachia. Its origins are disputed, theories ranging from a shepherd game to a war game.

In 1899, Spiru Haret, the minister of education decided that oină was to be played in schools in physical education classes. He organized the first annual oină competitions.

The Romanian Oină Federation ("Federaţia Română de Oină") was founded in 1932, and was reactivated at the beginning of the 1950s, after a brief period when it was dissolved.

Today, there are two oină federations: one in Bucharest, Romania and another one in Chişinău, Moldova.

The pitch is a rectangle, 70m long by 32m wide divided into:

The attacking side player that has commenced a run will have to cross the following four lines in order:

The in game area is further split into the advance and return triangles and squares. At the intersection of the lines inside the game area and the pitch limits or other lines within the game area, there are circles which determine the positions of the midfielders ("mijlocaşi") and side players ("mărginaşi"). The 1m and 3m semicircles are used for batting and serving. A waiting line is drawn for attacking players to wait their turn to bat.