Gintas Simkus was arrested at his Manchester home after police spotted a suspicious van in the car park at Morrisons supermarket, in Buxton.
The van, which had a large amount of clothing in the back, was traced to a house in Stonefield Drive, Manchester.
A second van at that address, which was registered to Simkus, was searched by police and also had a large amount of full charity bags in the back.
Simkus was charged with conspiracy to steal and money laundering.
The 39-year-old, originally from Lithuania but who was living in Polefield Grange, Manchester, denied both charges but was found guilty after a five-day trial at Derby Crown Court on Tuesday, January 28.
DC Gary Thomas, who led the investigation, said: “This was a despicable crime that struck at the heart of Derbyshire people’s generosity.
“Not only is this crime disgraceful but it has far-reaching consequences, affecting the most vulnerable people in society.
“The knock-on effect of this type of crime is that it will discourage members of the public from donating their much-needed unwanted clothing, which can be the lifeblood of charities across the country.
“I would urge people to continue their good work helping both local and national charities and not be deterred by the actions of this criminal.”
The offences and original arrest took place in 2010.