Truly was appointed following a three-way pitch with other undisclosed agencies.
It forms part of Alibaba.com’s $30m (£18.3m) year-long global marketing investment.
The business-to-business e-commerce company, which has customers including Argos and Tesco, is hoping to establish itself as the place where buyers can find quality products and suppliers online.
Truly London will handle creative, brand advertising, and media buying in EMEA.
Maggie Choo, director of Alibaba.com EMEA says it has already built a base of 2.5 million members across the region and it is growing by an average of 66% per year.
“However, with an estimated 23 million SMEs in Europe alone we see significant scope for helping many more small businesses across the region with cross-border trade,” Choo says.
In Europe it intends to launch a campaign which will include press, broadcast, online, PR, trade shows, training and viral marketing.
The account will be run out of Truly’s London and Bahrain offices.