South Waikato iwi Ngāti Raukawa has spent millions of dollars buying 47.5 percent of the 2500ha Ranginui Station.
The land near Mangakino is historically significant for the tribe and the purchase restores its ancestral ties to the area.
Ranginui Station is home to three dairy farms, a forestry block and dry stock.
It's been almost fully owned by local iwi Pouakani, which received the land in its treaty settlement.
Raukawa Settlement Trust chairperson Vanessa Eparaima said buying half of Ranginui Station was a smart investment.
"The land itself is in an area that's dear to Raukawa. The relationship with Pouakani Trust is a relationship where whakapapa [genealogy] is very close and it's also commercially advantageous to us as well."
Raukawa business unit manager Nigel Te Hiko said it was about much more than a commercial deal.
He said a lot of the tribe's culturally significant land is now in private ownership and so it has to find innovative ways to reconnect with those lands.
"Now we are able to step back in and say well actually this is our opportunity to demonstrate that we are actually kaitiaki [guardians] for this particular area."
Each year, the farm produces more than 800,000kg of milk solids.
Ms Eparaima was confident about the long-term returns from the farm, despite recent slumps in dairy prices.
"It's about Raukawa being around forever. It is a long-term investment," she said. "It is also an opportunity to be part of a farm that manages extremely well.
Raukawa is a stakeholder in the Waikato Regional Council's plan to clean up the Waikato River.
Mr Te Hiko said what impacted the river would impact the land, and vice versa.
The iwi wanted to demonstrate its environmental aspirations through the farm and to lead by example, he said.
A board of five will be created to run Ranginui Station. Two directors will be appointed by both Raukawa and Pouakani, and those directors will then appoint an independent chair.