The band, formed in 1917, will be seen by an estimated billion people across the globe who are expected to tune in to watch the ceremony.
The showstopping spectacular has been thought up by Oscar-winning director Danny Boyle and is entitled, Isle of Wonder.
The Chronicle understands the band has already been rehearsing for its role in the event which will take place on July 27.
Grimethorpe, whose members have performed at the Carnegie Hall in New York and Sydney Opera House, achieved international fame as the inspiration for the 1995 film Brassed Off, which followed the struggles of a fictional colliery band, Grimley, following the closure of the town's pit.
Yesterday press officers at the London Olympic organisers LOCOG were remaining tight-lipped about which bands and artistes were performing in the ceremony, saying: "We want it to be a surprise, we have explained all the details but we are keeping the rest of the show under wraps.
Full story in the Chronicle.
