EEW is responsible for supplying all of the 900-ton monopiles to Dong's 1.2GW Hornsea Project One offshore site in the North Sea.
Each monopile will have a diameter of 8.1 metres, EEW said.
Dong had planned to use suction-bucket foundations for one-third of the turbines at the site. But in June, the developer decided to use just a single foundation type to "optimise the execution of the project, and help ensure it will be built on time".
"Hornsea Project One will be the first wind farm in the world to have a capacity of more than 1GW and will provide enough energy for well over one million UK homes," said the project's engineering, procurement and construction director, Claus Norgaard.
"Using the same foundation solution for all turbines means we benefit from economies of scale and experience, and therefore maximise efficient construction of the project," Norgaard added.
The monopiles will support Siemens' 7MW offshore turbines and the project expected online in 2019. Preparatory onshore construction activity for the project started earlier this year.
The contract comes days after the foundation installation had been completed at Dong Energy's 659MW Walney Extension site in the Irish Sea, with the monopiles supplied by EEW.