Chairman of one of York's largest independent department stores and much-loved member of the community, Mr Thompson died of a heart attack while on holiday in Majorca.
Mr Thompson dedicated 55 years of his life to family business Barnitts, which was established in 1896 by George Barnitt.
He left school at the age of 15 to work at the store, which was bought by his father and uncle in 1913. Mr Thompson then took over the firm in 1955 at the age of 27 and was later joined by his children Paul and Sally who now help run the business.
Mr Thompson was holidaying in Majorca with his wife last week, when he suffered a heart attack and died, aged 70.
BHF-BSSA Group ceo Alan Hawkins said of the news: "Barnitts store is a flagship of the BHF-BSSA Group and Ian Thompson will be sadly missed by the trade and even more so by his family.
"What a difference a year makes. Last year Ian was showing members around his business as part of our AGM held in York. Ian was justifiably proud of his business which he ran with his family. A massive loss to us all."
Local news reports have also paid tribute to Mr Thompson, with one describing him as the "heart and soul" of York's retail community.
York business forum chairman and fellow retailer Adam Sinclair told The York Press that Mr Thompson was a "lovely and humble" man. He added; "He gave his heart and soul to his family and the family within the Barnitts business. He built one of the most exciting independent hardware businesses in Europe and everybody in York respected and admired him and his business."