The facility, which is for the development and testing of blades, currently has a staff of 200. The company is constructing a new building to house the facility, which will be completed in June.
A Vestas spokesman told Windpower Monthly: "Vestas currently employs 200 people in our R&D facilities on the Isle of Wight, and we are expanding to potentially house 400."
He added that the initial stage of expansion would involve fewer than 100 new staff.
In 2009 Vestas closed its blade factory on the Isle of Wight, blaming the UK planning system for limiting wind farm development in the country.
It was awarded £3 million in grants by the British government and over £3 million funding from the South East England Development Agency the same year to expand its R&D facilities on the island.