Newbridge is a thirteenth-century bridge carrying the A415 road over the River Thames in Oxfordshire, between Abingdon and Witney, close to the Thames' confluence with the River Windrush. It is one of the two oldest surviving bridges across the Thames.

There is a pub at either end of the bridge: "The Rose Revived" on the north bank, and "The Maybush" on the south bank. The bridge consists two spans, where the northern span crosses the river and the southern span, south of the Maybush, is dry underneath except when the river floods.

The bridge dates from the 13th century and is constructed with Taynton stone in the same way as Radcot Bridge, which is slightly older. They were built by monks on the orders of King John in order to improve communications between the wool towns in the south of England, and the Cotswold farms. This one was named "New Bridge" as it was the youngest out of the three bridges built at the time (the third being the Lechlade bridge, replaced in the nineteenth century). It was also very much longer than it is now, with 51 arches and being 664 m long, compared with the current 12 arches.

Whether Newbridge or Radcot Bridge is the oldest surviving crossing of the Thames is debatable. While Radcot Bridge is the older structure, it was extensively damaged during the Wars of the Roses and had to be greatly rebuilt. Furthermore, following re-routing of the Thames in 1787, the Radcot bridge no longer crosses the main channel of the river.

In 1644, during the English Civil War, the Battle of Newbridge was fought on the banks of the river. Roundhead William Waller attempted to cross in order to surround Oxford and capture King Charles, but was defeated.

The bridge is controlled by traffic lights, not being designed to carry modern traffic, and an 18-tonne weight limit is imposed to protect its weakening structure. Further reductions are considered likely by local authorities. According to a 1996 survey, one of the arches is only capable of carrying its own weight, though it was decided that there was enough leeway to allow traffic to continue across the bridge. The likelihood of collapse is considered slim.