Australia's longest-serving independent senator Brian Harradine has died in Hobart aged 79 after a long illness.

The former Tasmanian senator had suffered several strokes in the past few years and died at home.

He is survived by his second wife, 13 children and grandchildren.

Mr Harradine was known as "the father of the Senate", serving six terms as an independent after he was elected in 1975.

The devout Catholic was known for his anti-abortion and anti-pornography stance.

He listed his greatest achievements as the cash deal for Tasmania that came as part of the partial sale of Telstra, and brokering the Wik native title agreement to avoid a race-based election.

Born in South Australia, he moved to Tasmania in 1959 and worked as a union official, heading up the Trades and Labor Council for 12 years.

In 1968 he was barred from sitting on the Labor Party's federal executive for saying some of them were the friends of communists.

His Labor links were severed in 1975 after the party's socialist Left had him expelled.

"It came as a bitter blow, I've got many faults, one of them is not lying down and whimpering," he said at the time.

In the same year he was elected to the Senate as an independent.

Senator used balance of power to secure funds for Tasmania

By the early 1980s Mr Harradine held the balance of power in the Senate and was not afraid to use it.

Known as a wily negotiator, he secured $350 million for Tasmania in exchange for supporting the part sale of Telstra.

In 2004, Mr Harradine told the ABC's Stateline program what he was proud of achieving in the native title Wik negotiations with the Howard government.

"Their threshold test excluded the right, excluded the victims of locked-gates policy and also the Stolen Generation, from even claiming native title, and I said no," he told the program.

"They wanted the Act to only have six years' life, and I said no.

"And they wanted to abolish the right to negotiate and I certainly said no to that and improved the circumstances, and indeed established a system of Indigenous land use agreements.

"I did prevent a race-based election because the government was threatening a double dissolution over the matter.

"And just before then, up in Queensland there was a whole heap of people who were against the rights of the Aboriginals who had been elected."

Harradine remembered as man of integrity and commitment

He was also know for his opposition to stem cell research.

"If you treat the tiniest member of the human family as a laboratory rat or experimental tool, you are going down the drain," he said.

Mr Harradine retired due to ill health in 2005.

Tasmania's Catholic Archbishop said Mr Harradine should be an inspiration to those trying to stand by their principles in public office.

Archbishop Julian Porteous said the former senator was deeply opposed to abortion and the introduction of the RU486 pill, and kept those convictions in politics.

"I think he was an outstanding man in terms of having some very strong, clear principles on a number of issues and he stood by them," he said.

"I think people had great respect for him because of that."

In a statement, senior Tasmanian Liberal Senator Eric Abetz said Mr Harradine was a man of integrity and commitment.

"Brian's life was one of dedication to values and principles, humble service to his fellow man and a love for all things Tasmanian," he said.

"His crafty negotiating skills, especially when holding the balance of power in the Senate, delivered huge dividends for his beloved state of Tasmania, especially with the Telstra fund."

Prime Minister Tony Abbott said Mr Harradine made a "strong and effective contribution" to both the Senate and Tasmania.

"[He] was proud of his family, proud of his state and proud of the Parliament that he served," he said in a statement.

"My thoughts are with his wife, Marian, and their children and grandchildren."

Tasmania's Deputy Premier Jeremy Rockliff has also paid tribute.

"He was justly known as a man of integrity who believed in the dignity of all people," he said in a statement.

"He was a fighter for Tasmania and he was held in high esteem by all sides of the political debate."