The World War Two planes will drop more than 200,000 poppies following a service at the Tank Museum in Bovington on Remembrance Sunday.
The flowers will be cast from the vintage bi-planes as they fly past during the two-minute silence.
The service at the museum will be open to members of the public.
Former Fleet Air Arm pilot Kevin Crumplin, who owns and restores the planes, said it was unusual to see the three Tiger Moths flying in formation.
"We would normally fly two together, or just one.
"It will be the first time we do a poppy drop."
Mr Crumplin said he was happy to organise the flypast, which had been at the request of the Army.
Three Tiger Moth aircraft are to drop thousands of poppies from the skies above Dorset in memory of servicemen and women who died in the line of duty.