The new ferries will be modified, based on staff and passenger feedback, and will have an additional 80 seats, an extra scenic viewing platform, and increased designated cabin baggage.
They will be 34m long and travel at 26 knots.
Fullers chief executive Doug Hudson said it was important to the company and the shareholder that the vessels were built locally, providing a boost to the regional economy.
"Q-West is known for its innovative and quality builds, and with such a large contract we were determined to ensure the local market benefited from the investment," he said.
"We knew that the team at Q-West could deliver on what is a maritime milestone for us."
The first vessel is expected to be launched in October 2016, and the second is planned to be christened in April 2017.
Q-West managing director and NZ Marine Industry Association president Myles Fothergill said they would be employing 20 extra staff to work on the construction, with the core team who managed the Te Kotuku.
"We're rapt, obviously," he said. "We've taken on more staff. That's always good news, especially for the region."
Mr Fothergill said the regions had taken "a bit of a beating" ecomomically over the past few years. The firm is to look nationwide for staff with high skill levels needed for the project.
"It's always been part of Fullers' plan to modernise their fleet and start replacing some of their older vessels," Mr Fothergill said.
"We've got a really good relationship with Fullers. They're a very good company to work with. Fullers is offshore-owned ... so we've got an offshore owner who's very, very focused on looking after the local New Zealand economy. Anywhere that any of those companies can buy locally, he's pushing for that. "We're really pleased that Fullers have that - they've got confidence in the New Zealand industry and in particular our company, of course."
Mr Fothergill said they worked on the Te Kotuku and delivered it last year, and the fact Fullers wanted to use Q-West again was a compliment to staff.
"That's a real testament to all the team at Q-West that we're able to provide exceptionally high quality that they recognise as being world class, so there's no need for them to go anywhere else, just work with us."
NZ Marine Industry Association executive director Peter Busfield said the order for two ferries boosted an already vibrant marine sector.
"The industry is currently worth $1.7 billion to the New Zealand economy," he said.
"The industry congratulates Fullers for recognising the high quality and performance of Q-West vessels and other New Zealand equipment suppliers with this latest order."
The move is a response to the estimated 1000 daily commuters on the Auckland-Waiheke route as well as growing tourism in Auckland.
Mr Hudson said the builds were the next evolution of the Fullers fleet as it invested in more reliable travel.