Cabinet minister Georgina te Heuheu has confirmed she will retire at the election.
In a statement she said now was the time to go with the party was in "good heart".
Te Heuheu has been in Parliament for 15 years and said she came in when the National Party decided to settle Treaty claims and lift Maori participation.
"Politics is a brutal game at times. I have tried to focus on the issues rather than personalities. Politics can be all-encompassing and often you forget there are other things in life. "
She said she looked forward to spending time with her family and seeking other challenges.
Te Heuheu said she was proud to have served on Prime Minister John Key's Cabinet.
"I also hope New Zealanders give him a good mandate to pursue a vision for New Zealand that recognises that every New Zealander has an important role to play in building a strong nation."
She is current Minister of Courts, Disarmament, Pacific Island Affairs and Associate Minister of Maori Affairs.
From 1998 to 1999 she was Minister of Women’s Affairs, Associate Minister for Treaty of Waitangi Negotiations and Associate Minister of Health.
Before entering Parliament she was a lawyer in Rotorua and Wellington and was admitted to the High Court.
Prime Minister John Key thanked te Heuheu for her service and said she would retain her portfolios until the election in November.
“I want to thank Georgina for the contribution she has made in her career in national politics over the last 15 years, and also for her public service in a myriad of other roles."
What do you think of claims Kiwis have been misled about mass surveillance?Related story: US spy base in NZ?