Osney Mill Marina (also known as Osney Marina) is a private marina situated on a 500-metre island in the River Thames at Oxford, England. The island was created in the Middle Ages to supply water to the now-disused Osney Mill.

Access to the main Thames is at the southern end of the marina, with Osney Lock lying to the north. The site is reached via Mill Street off Botley Road, close to the former Osney Abbey and Oxford railway station.

The marina accommodates up to 40 moorings alongside the island and sits within a gated residential development. Boat maintenance and light engineering services are available on site.

Its central Oxford location places it within easy reach of the city centre by foot.