The 30,000sqm building has 75 rooms, more than 50 of which are leased for low rents by various musicians, artists, photographers, dance and martial arts studios as well as community learning organisations.
Even the coal bunkers and toilet blocks are rented for storage space.
Building manager Kathryn Olcott confirmed the building was for sale and believed an offer might already have been made on the building.
However, it was not known who had made it, or how much was offered.
It was also unknown which real estate company it was being sold through.
"Nothing has been confirmed. We don’t know what the plans are," she said.
"Whenever there is a group of people whose livelihoods are totally dependent on the good rents in the community that exist, it’s unsettling."
When the property was bought by Americans Ray and Gwynn Joseph in 2000, there was talk of it being turned into apartments or a hotel, but instead it became a hub for community groups, sports clubs and small businesses.
Now that the Josephs are looking to sell, there are fears a new owner may evict the tenants and again focus on turning it into apartments or a hotel.
Tenant Adrian Mann said a small group of tenants had banded together to look at establishing a trust to raise money and make an offer on the building, in a bid to keep it running for the future of the arts community.
"If everyone in Dunedin could give $30, that could be enough to buy it."
If the "trust" was unable to buy the building, he hoped it would be sold to someone who had an interest in the arts and would keep operating it as a supporter of the arts.
He said many tenants were scared of the sale because they did not know how it would affect their businesses.
"It’s a pretty big arts community in here.
"The main thing about this place is people can come in here and give their passion a go, and if it doesn’t work out, it doesn’t work out, but at least they’ve given it a go.
"Some people go on to make careers out of what they’ve wanted to do and what they’ve loved.
"They would never get that opportunity anywhere else because of the cost of rent."
Mr Mann said it was still too early to say what the future held for the building, but it would be sad if it was redeveloped or closed to the arts community.
"I would feel really sad for Dunedin. It would be a huge blow for the arts community."
Mr and Mrs Joseph were unable to be contacted yesterday.
The building’s foundation stone was laid on March 20, 1913, and by 1955 the school had grown into the largest in the country, with about 2500 pupils.
But by 1966, the tertiary arm of the college had renamed itself Otago Polytechnic and moved out of the building, and in 1974 the secondary school followed suit and became Logan Park High School.
Since then, the King Edward Technical College buildings, now known as King Edward Court, have been privately owned.
