Gulliver's Valley Resort, on the Pit House West site, received planning permission by Rotherham Council's planning committee last month.
The approval sparked a 21-day period in which the Secretary of State for Communities & Local Government, Sajid Javid MP, could "call-in" the decision.
However, with this period of time passing without objection, work is now set to commence on the site to the delight of the family owners.
Managing director of Gulliver's theme park business, Julie Dalton, said: "After a good two years of hard work, it's absolutely wonderful to know that our vision for Gulliver's fourth UK theme park is going to become a reality. We're all absolutely delighted.
"Throughout the planning process, I and my senior staff have taken part in several consultation events around the local area, giving local residents the chance to comment on our plans.
"We worked closely with Rotherham Council and Highways England to ensure our planning application did not negatively impact on local access routes and amended plans to reduce the visual impact of our larger attractions.
"It's incredibly satisfying that local councillors voted unanimously in favour of our proposals. This is an exciting time in Gulliver's history."
In February, planning officers recommended the plans which include the main theme park, a water play zone, climbing centre, glades attraction and an education and ecology centre, be approved.
This is despite the land being within the green belt, where development is usually forbidden.
The new development is set to benefit the local economy with the multi-million pound project expected to create around 400 jobs.
Ms Dalton added: "Our Gulliver's Valley development will give the area a huge economic boost as we look to use a local supply chain and bring tourism pounds into the local economy.
"Add to that the number of local jobs it will create - up to 255 full time equivalent posts - and it will be a real positive for the Rother Valley community."
Gulliver's aim to open their brand-new Valley Resort in 2020 which offers family-friendly accommodation in the shape of glamping, self-catering woodland lodges and the central Lilliput Castle Hotel.
The development will also encompass Gully's Dream Village, a community where children with life threatening illnesses can be given the chance to enjoy cost-free respite in a magical environment.
Rotherham Council's cabinet member for Jobs and the Local Economy Cllr Denise Lelliott said the latest development was ‘great news' and paved the way for the development to go ahead.
She added: "This decision is the culmination of more than two years-worth of planning by Gulliver's, including the Council agreeing to sell the land for the development to Gulliver's in 2015.
We now look forward to seeing Gulliver's plans being brought to fruition. As well as being a fantastic facility for local families, the Valley Resort will result in a massive boost to the area and our local economy.
It will bring in visitors, provide jobs for local people, and complement the existing activities at nearby Rother Valley Country Park.
"This is a family-run business with a proven track record for building and operating family entertainment developments and we are very proud and excited that Gulliver's has chosen the borough to develop their resort."