DLKW won a four-way battle that involved Joshua and DFGW, to become the auction site's first creative advertising agency.
The agency's brief is to develop brand marketing and offline activity, which will break later this year. The business is estimated to be worth £3 million a year.
The appointment of DLKW coincides with the announcement that eBay has hired Iain Hildreth as the head of brand and offline marketing. Hildreth joins from Barclays, where he was the head of brand experience, and will report to eBay's UK marketing director, Simon Darling.
Darling said: "We are delighted at the appointment of DLKW and we are confident it is the ideal partner to develop strategies that will take our brand forward in 2004. I'd like to extend a huge thank you to all of the agencies that participated in the process."
EBay kicked off the review in December following Darling's appointment.
He joined in July from Unilever, where he was the interactive marketing chief, and replaced Linda Campbell.