Synergy's van, housing all the band's equipment, was taken from the driveway of a house in Whiston, Rotherham, overnight on Tuesday.
The white transit van, with the registration number NV08 NGZ, was taken alongside a white Mini Cooper and contents of the house they were parked outside.
Band member Carl Wragg, from Doncaster, has posted a list of all the band's stolen equipment on Facebook.
He said it took 10 years to build up the collection, including four Fender Stratocaster guitars, amps and speakers, a pedal board, microphones, stands, a mixing desk, PA system, lighting equipment and gigging clothes.
He said: "In terms of the white transit van, it was full of musical equipment. All gone.
"Worked for a decade to build this up and now some scumbag has it."
He thanked fellow musicians and bands for offering to loan equipment while the band's insurance claim is going through and urged people to raise awareness of the theft in the hope of tracking some of the stolen items down.
"Please please share this as much as possible - especially with music shops, secondhand music instrument dealers, cash converters etc and lets see if we can get any of it back," he said.
"Me and the lads are devastated."
Anyone with information should call South Yorkshire Police on 101.