The Publicis Groupe agency kept hold of the business after fending off Vizeum, Maxus, MCHI and Walker media.
The process is believed to have involved tough negotiations. MediaVest is understood to have been given set targets for the first half of 2011, upon which the future of the business rests.
The Starcom MediaVest Group agency has held the account for more than 10 years, stretching back to the time when Cineworld was called UGC.
Cineworld currently spends an estimated £1m on media, but is set to raise this in the New Year, when it promotes site openings and its investment in digital screen technology.
Cineworld's revenue in the six months to 1 July rose 3.8 per cent to £162m, with the company crediting films such as 'Avatar' in 3D as contributing to this increase.