Speaking to students and staff in the school's sensory courtyard on Wednesday, Mr Dixon said he was delighted to officially open the school.

"I opened a school yesterday in Gippsland but I think this is the best school I've ever opened," he said.

"You guys have the best school in Victoria.

"It's great to be here at Horsham Special School with so many special, special people."

School principal Matt Copping said he was pleased to celebrate the school's opening.

"It's just fantastic for a government school and for a specialist school," he said.

There are 71 students at the school, which has been open since July last year.

Mr Copping said the state-of-the-art building had a range of facilities which would benefit students, including a commercial kitchen.

"The biggest feature is the sensory courtyard which has a number of areas in it that enable us to develop some of the senses that develop innately in most people but not if you have a cognitive disability," he said.

"It's an amazing building. It's a bit of a 'wow' building, but it's functional as well and we're really able to up the ante on the type of curriculum programs we can provide for our students, especially in specialist and therapeutic areas."

Mr Copping paid tribute to former principal Rhonda Coffey and school council president Max Cuddihy who he said were instrumental in getting the project off the ground.

Member for Lowan Hugh Delahunty also spoke at the ceremony and nominated the project as a career highlight.

"This has been one of the great joys of my life," he said.