It won the estimated six-figure contract after a competitive pitch and will manage a range of outdoor media at the Battersea site.
Ocean will officially launch the site this autumn, working with architect Zac Monroe, who designed Ocean's recently launched Tower 400 on the A40, to develop panels for prestige brands.
Advertising opportunities will remain in place for the duration of the former power station's redevelopment into a mix of residential, office, leisure and retail developments.
The site is one of the largest urban regeneration projects in central London. It was acquired by Real Estate Opportunities in December 2006 for £400m. It comprises 38 acres, including the six-acre power station, the largest brick building in Europe, and a riverside frontage of 380 metres.
The site was originally bought for £10m in 1993 by the Hong Kong-based Hwang family.