The 700 job Menai Science Park will be kick-started with a £10m EU funding boost.
Led by Bangor University the park has already been awarded £10m from the Welsh Governmentand this further funding provides the remainder of the investment needed for the first phase to start.
The park at Gaerwen - which received outline planning permission in May - will focus predominantly on low carbon and renewable energy businesses, complementing Energy Island.
It will encourage collaboration between the private sector and research organisations with the aim of creating hundreds of job opportunities.
The scheme will see around 100 people work on the construction and the aim is for 700 roles to be based on the park in the long term.
First Minister Carwyn Jones said: “I am delighted to announce £10m EU Funds for this exciting new Menai Science Park.
"It will provide a dynamic and supportive environment for low carbon energy businesses in North West Wales.
"The investment will also support job creation, helping secure a sustainable future for Angleseyand contributing to economic growth for the area and the wider Welsh economy.”
Construction is set to begin during summer 2016 with the first businesses expected to move in during early 2018.
Economy Minister Edwina Hart added: “The Welsh Government is committed to supporting science and innovation, which is vital to creating economic growth and high-quality jobs. I am very pleased that all the funding is now in place to enable this exciting project to proceed. “
M-SParc director Ieuan Wyn Jones said: “The announcement today, combined with the Welsh Government’s investment is not only a great boost for M-SParc, but also for future scientific endeavour in north Wales.
“We now have the funding place to deliver a truly unique resource for the region.
“This will not only offer high value job opportunities locally, but also benefit the whole of the North Wales economy by creating an inspirational work environment to attract local businesses and those looking to relocate to the region.
“We also now have the first designs for the first building on site as we prepare to submit a full planning application to Anglesey Council before the end of the year.”
M-SParc will also be holding a public consultation event to display the proposed designs for the first building on site.
This will take place on Thursday October 29 between 10.30am-7.30pm in the vestry of Disgwylfa chapel in Gaerwen.
Vice Chancellor of Bangor University and Chair of M-SParc Professor John G. Hughes said: “M-SParc is gaining momentum and the funding agreement is great news.
“The park is set to become a fantastic and inspiring place to spark innovation and create a hi-tech economy in the area.
“Together with the expertise of Bangor University and our ambitious plans to further develop our strengths in science, we are in a strong position to make a big difference to the area.”