The Southern Field Days has entered a new era.

A new $1.5 million events centre, which will house 180 small stallholders, was officially opened on Saturday by Invercargill MP Eric Roy.

Mr Roy, who was one of the original committee members, said he was "gobsmacked" by the scale of the 5000 square metre events centre which was built by Chris Broadhead Construction.

"We had a vision we'd get here someday. It's fantastic to think that the growth of the event can justify such an impressive building," Mr Roy said.

About 150 people, including past and present committee members, original exhibitors and builders attended the opening of the events centre at Waimumu, near Gore.

The events centre would not only weather-proof the event for the small stallholders but would also provide a safe and secure place for them to showcase their wares.

Mr Roy helped establish the first Southern Field Days which was held in 1982 with just 54 exhibitors.

The event had grown to become the South Island's largest agricultural event and almost 800 exhibitors would attend the 2014 field days from February 12 to 14.

"I knew we were on to something but I never thought it would be as spectacular as this," Mr Roy said.

Southern Field Days chairman Mark Dillon said the committee came up with the idea to build the events centre two years ago.

"It's going to look really impressive on the day when all the sites are set up," he said.

Mr Roy described the Southern Field Days as a "sophisticated expo" which he believed would continue to go from strength to strength. "One day it might even surpass Mystery Creek [the National Agricultural Fieldays]."

Mr Dillon said the events centre, which could hold up to 6000 people, would be available for hire after the field days.