The block of land, on the five-star resort's western boundary, will allow it to expand its residential complex and also develop its existing 27-hole golf course, which can be played in a mix of three nine-hole courses, into two full size 18 hole courses.
Millbrook property and development manager Ben O'Malley said the 66ha block was bought from farmers Ian and Pip Macauley, who wanted to downsize as they neared retirement.
The terrain is a mix of flat to steep hill country which Mr O'Malley said offered both challenges and opportunity.
''Parts are not suited to golf or real estate, which is part of its beauty.''
The process of rezoning the land from rural general to Millbrook resort zone would began shortly, and could take between 18 months and three years. Earthworks and construction would then begin.
Mr O'Malley said how the land was eventually used depended on its sensitivity, but he expected a mix of residential, golf course, revegetation with indigenous plants and retaining livestock grazing for pasture control on areas too steep to use machinery.
Millbrook's residential zone already extended up to the boundary of the new block.
Mill Stream flows through the newly acquired land before entering Millbrook and Mr O'Malley said this provided opportunity for continued riparian and habitat restoration which has attracted more fish and bird life to the stream.
The new golf course would allow the resort to tap into the growing golf tourism market, and its proposed layout would enable Millbrook to offer New Zealand's only two-course resort complex while also doubling its capacity.
Golf course designer and former professional golfer Greg Turner has already started work on incorporating the new nine-hole course into the resort's existing course.
Millbrook is owned by the Japan-based Ishii family, who bought the land in 1988 and opened the resort in 1994 with the goal of developing ''the best golf and lifestyle resort in the world''.
The family made its money in traditional and digital art supplies.
