The three-person team, which will focus on helping consumer brands drive sales on Amazon, is led by Beattie's digital marketing director Daniela Young.
Third-party sales via Amazon Marketplace are worth $160bn each year and the platform generates annual ad revenue of abour $12bn.
Brands are investing more of their marketing budgets into the Amazon ecosystem as consumers increasingly use the company's ecommerce platform as a first port of call when searching for products.
Beattie chief executive Laurna Woods said the agency plans to rapidly grow the fledging Amazon advertising team, and has not ruled out mergers and acquisitions.
"Amazon is the biggest search-to-view and search-to-buy engine in the world and there are only a handful of specialist agencies out there," she said. "Our goal is to become the dominant player in the UK through a mixture of organic, merger and acquisition growth."
Young explained that there are more than 2.5 million sellers currently active on Amazon, about 25,000 of them with sales of more than $1m.
"Amazon is a marketplace that requires specific expertise – that might be why it has not proved attractive to traditional digital agencies," she said. "The algorithm is constantly changing and you need to know what you're doing or you'll get your fingers burned.
"We have taken the time to analyse, perfect and deliver strategies for success on Amazon and we're in a position to roll out that expertise to help newbies, but [also], more importantly, big brands that are not gaining the results they anticipated."