The thieves targeted the I Wish It Could Be Christmas Every Day musician's long-time sound engineer Bob Collinson - taking a truck full of custom-made guitars and amps while the vehicle was parked up overnight at his business premises in Leeds.
Click here to watch CCTV footage of the gang stealing the truck full of Roy's sound equipmentCCTV taken from Bob's business, Yorkshire Audio in Beeston, shows the men climb over the 6ft locked gates before driving the Iveco Eurocargo truck away demolishing a wall in the process.
The theft has left the businessman devastated - and the singer has cancelled a gig in Hull as he cannot perform without the equipment, which includes a one-of-a-kind Marshall stack amplifier that was custom-made for him.
Bob has worked with the star for years and was accompanying him on tour. The theft occurred when the truck was parked at his Beeston premises overnight ahead of the concert at Hull City Hall.
"They have taken thousands of pounds' worth of sound equipment," said Bob's daughter Sharon Collinson.
"The red Marshall stack amplifier is so distinctive - it's the only one of its kind in the world and they wouldn't be able to sell it. Some of the guitars were ones Roy's used for 50 years and he won't tour without them. He's devastated.
"It's my dad's whole business and entire life - if the insurers don't pay out then it will fold."
The Eurocargo truck has a white box and does not display a company logo.
"There were three or four of them, they climbed over the wall and hotwired the truck. We think they also looked around the garden a few days before. It's the first time Dad has been targeted and he's had the business all his life.
"We have serial numbers for all the stolen items and they are just so rare - it would be really difficult for them to sell them on. One mixing deck is worth about £30,000 and the customised speaker is priceless. We think they might have been after the truck rather than the sound equipment and maybe just expected to find tools inside.
"We've contacted all music shops to alert them.
"My dad came home for a rest after the last show, and was due to drive the truck to Hull for the next gig. Roy's cancelled it now. He might not tour ever again without his life's work."
West Yorkshire Police are investigating.