The event, which will be coordinated by sports marketing agency Limelight Sports, is called the Poppy Match and will take place on February 23 at East London's Hackney Marshes.
The event has been devised to attract younger supporters to the Legion, which was set up to protect the interests, welfare and memory of British serving and ex-Service people and their dependants.
The initiative will take place on five oversized pitches, with 20 games and 40 teams all simultaneously playing on the same day.
Each pitch will be divided into five zones, with the 30-man squads split into teams of six. The teams will be responsible for attacking or defending their zone as they try to pass the ball through the pitch towards the goal.
An added twist has been included, with the prospect of five balls being in play on the pitch at any one time.
Andy Anstey, business development director for Limelight Sports, said: "When devising charity fundraising events it is important to make them relevant to the cause, widely accessible and with room for growth.
"The Poppy Match is a fantastic initiative that really captures the imagination and hopefully we will help The Royal British Legion to turn this new scheme into a regular annual event."
Teresa Greener, head of events at The Royal British Legion, said: "We are thrilled to be working on this unique and exciting event -- a fantastic opportunity for people to be involved in a brand new way to support our vital work."