The lease and access agreements are yet to be finalised.
The iwi group were granted the right to purchase Crown-owned land from Corrections in 2008, after singing The Central North Island Forest Collective Settlement deed.
The iwi partnership includes two major Tuwharetoa forestry trusts, Tuwharetoa farm trusts, and a collective hapu entity.
Mr Tahau said the deal had major strategic and commercial benefits for the iwi partners but, most importantly, the purchase saw the return of Tuwharetoa whenua (land).
"This is a great milestone for our iwi and we are really pleased that the partnership has been able to work closely to get to this point.
"There are several important wahi tapu (sacred areas) on the land, and two of our rivers, the Waiotaka and Tongariro, run through it also.
"Purchasing this property and agreeing a lease-back is a major benefit for Tuwharetoa, and will support our economic, social and cultural development," Mr Tahau said.
Mr Lotu-liga said he was pleased to be returning such important land to the iwi.
"The deal, which has been in negotiation since 2008, is an example of the co-operation between the Crown and iwi." The deal ends the Tuwharetoa Deferred Settlement Process, which was part of the 2008 Central North Island Treaty Settlement.
Corrections and the trust signed the sale and purchase agreement, which will be formalised on June 30.