The club said they were "devastated" by the death of one of their most loyal backers who was "a very close and inspirational friend".

Thompson, 67, won much admiration in the football world and was seen as a champion of the smaller clubs in the Scottish Premier League.

Despite his debilitating illness over the past few years, he continued with his duties at Tannadice as long as he could.

He also insisted on supporting his team in person as much as possible, both home and away.

The club said in a statement on their official website: "It is with great sadness that Dundee United announce the death of chairman Eddie Thompson, who died today after a long illness borne with great fortitude, much bravery and a dogged determination to carry out his responsibilities at Tannadice for as long as possible."

The news comes only three days after the death of his son-in-law Ken Mitchell, 38, who died in a motorcycle accident.

Thompson had been battling cancer over the past few years and received specialist treatment at Ninewells Hospital, Dundee.

But despite these efforts, the disease could not be prevented from spreading.

He is survived by his wife Cath, children Justine and Stephen and four grandchildren.

Born in Glasgow in 1940, he moved to Dundee in 1964 and began to support the club.

He was a trained accountant and successful businessman and was keen to bring these business links to bear at Dundee United.

Thompson became chairman and owner in September 2002 after acquiring a majority shareholding.

Since that day, he has ploughed millions of pounds of his own money into Dundee United.

In June 2007, the club was mired in record levels of debt, which stood at £2.7million.

But despite his financial backing and business-like approach to handling the side, he saw himself above all as a supporter and believed Dundee United fans were the club's true owners.

He was once quoted as saying: "You can change your wife, your house, your car, but you can never change your team.

"Chairmen come and go, boards come and go, but the fans remain. They are the one true constant."

One of the stands at Tannadice was named after him earlier this year and thousands of Dundee United fans wore "One Eddie Thompson" T-shirts at this year's CIS Cup final.

Motherwell chairman John Boyle paid tribute to Thompson as a champion of the smaller clubs in Scotland's top flight.

"He fought for his club, he was so enthusiastic and so passionate," Boyle told BBC Radio Scotland. "He was an inspiration to us.

"There was absolutely no question that, as he said, he was the custodian for the fans.

"Dundee United went through a very, very turbulent time and he was a bit of stability for the club.

"They have achieved marvels in the last six or seven years, largely due to his influence. The players, the manager and the fans all looked up to him so much.

"He has left the club in a tremendously good nick.

"He fought for all of the smaller clubs. He was a director of the SPL for many years and everyone will tell you, they may have disagreed with him, but there was enormous respect for him."

Mike Barile, associate director of the Dundee United supporters' group Arab Trust and a close friend of Thompson, described him as "just a lovely, lovely man".

Barile said: "Eddie was so passionate about his football team, and through his hard work and determination he proved his doubters wrong and turned things around here.

"He was a real workaholic and that explains a lot of his success in business - once he decided what he wanted to do that is what he did.

"But at the same time he also allocated time to his wife and family, and I can remember my wife once remarking about what a gentleman he was with Cath.

"Whether Eddie was speaking to a taxi driver or whoever, he gave that individual his full attention and was genuinely interested in them - that was a remarkable gift."

United supporters paid tribute to Thompson's "passion, commitment, tenacity and determination" for the club.

A statement from the Federation of Dundee United Supporters' Clubs added: "We have lost a wonderful father figure whose massive physical, emotional and financial contribution will always be revered amongst us.

"The courage, bravery and devotion to our team shown by Eddie during the latter stages of his illness dispels the myth that there are no heroes anymore - Eddie Thompson is a hero to all of us.

"We are all heartbroken today. The heartfelt love and sympathy of every Dundee United FC supporter go out to Cath, Stephen, Justine and the family."

Scottish Football Association chief executive Gordon Smith said: "Everyone at the Scottish FA is extremely saddened to hear about the passing of Dundee United chairman Eddie Thompson.

"Our thoughts are with his family, his friends and everyone at the club at this terribly sad time.

"Eddie was a man who loved the game and was passionate about bringing success to the club he loved.

"You need only look at the way the fans reacted at the CIS Cup final earlier this year to see how much Dundee United meant to Eddie and how much Eddie meant to the club.

"He will be sorely missed."

Former Dundee United skipper Derek McInnes paid tribute to Thompson's work at Tannadice.

The St Johnstone manager said: "First and foremost my thoughts are with his family, he was a big family man.

"I don't think anyone could have done more in his time at a club, not just the financial side but his time.

"I think Dundee United are a better club for that.

"He worked so hard to generate money for the club.

"He was desperate for some sort of success and Dundee United have been a better club in the last few seasons. He has played his part in that as well as the manager, Craig Levein.

"On a personal level, when I got the manager's job at St Johnstone, the first letter that arrived to congratulate me was from Eddie Thompson. That was appreciated."

Dundee United manager Craig Levein paid tribute to his boss and close friend.

"We have lost someone I'd call a decent guy and as close as we've become, he is someone I wish I could have known a lot longer," he told the club website.

"As a chairman he could not have backed me any more than he did, but it is as a good man that I think of him.

"Over the next few days a lot will be said about him and what he achieved, but I really will remember him as a decent guy."

He went on: "We knew how ill the chairman was and we have been expecting this. That means in some ways you can steel yourself for it, but when it happens it is still terrible news.

"We are all very upset and right now there is not much I can say."