The fly-half – his country's leading points scorer at just 23 – has agreed to join international colleagues Martin Johnson, Lawrence Dallaglio and Jason Leonard for the night.
The night – at the Walkabout venue at Temple on the Embankment – is being sponsored by Tetley's, Official Beer of England Rugby, and is supported by Planet Rugby.
England captain Johnson and his colleagues will spend time chatting to supporters and signing autographs before three of them take to the stage to share stories and memories from their international careers and answer fans' questions.
The evening – Thursday, March 6 – is the latest in a series of Tetley's and Walkabout nights to raise money for Cunningham.
"This is a fantastic cause and the least the players could do was to turn out for Jarrod," said Johnson.
"I don't know him that well personally – though I remember playing against him and thinking he was something special - but the players who do know him say he is a really top bloke and he deserves all our support."
Walkabout Brand Manager Natalie Walter said: "We are delighted Jonny will be attending the evening. He's a legend of the game despite his youth and I'm sure fans will want to meet him as well as the other guys.
"It is a fantastic opportunity for fans of English rugby to meet some true modern-day legends of the game, to have a great time and to raise money for a really good cause in the process."
Tetley's sponsorship manager Gareth Roberts said: "Jarrod was a great player who thrilled crowds throughout the Premiership and for him to be diagnosed with Motor Neurone Disease is very sad.
"It's great that the players have agreed to support him and we obviously hope that London's rugby fans will do so too."
The former London Irish and NZ Maoris player was diagnosed with MND in the northern hemisphere summer.
Medical opinion suggests MND is always fatal and kills, on average, within 14 months of diagnosis.
Despite that, Cunningham is battling to beat the condition and recently met an American MND patient who has apparently succeeded in reversing his symptoms.
Tickets to the event – priced at £10 – are already selling quickly. They are available from the venue, which can be called on 020 7395 3690 or online by CLICKING HERE.