The O2 Arena in London will host a fight on October 8, almost 30 years after their fathers fought in one of the most famous rivalries in British boxing history.
Each fight will have a catch weight limit.
Since joining the professional ranks in 2011, he has recorded 32 wins and two losses.
Benn has won 21 bouts since becoming a professional boxer.
The announcement reignites the feud between the Benn and Eubank families.
Both of their fathers fought, with their father winning the first one. The second drew a split decision.
Both men were household name due to their bitter rivalry, which generated huge interest.
The second episode was watched by over 15 million people in the UK.
He has followed the same path as I have. I'm aware of his struggles. He said that he was living in the shadow of a legend and trying to break out of it.
The biggest fight of my career is this one.
Benn knows a lot about the family history. He said he couldn't pass up the chance to fight for the legacy.
"My team and I had other options on the table as I'm currently ranked top five with all governing bodies at the weight class and no doubt I'm looking for a world championship fight very soon, but this fight is embedded with so much history and I know it's one
It's more than titles and rankings, this is unfinished business between our families.
Eddie Hearn is the promoter of Benn. People have been talking about this moment ever since they both turned professional.
It was thought that the clear weight difference between the two would prevent the fight from happening.
In February, Eubank Jr played down the chances of a fight with Benn, saying it could possibly happen in a couple of years. Eddie Hearn distanced himself from the fight a few weeks ago.
Benn and Eubank Jr both box at the same weight.
They will have to make some adjustments to their fighting weight because of the catchweight limit. The day before the fight, they will be weighed in.
If a rehydration clause is included in the contract, there will be a limit to how much weight each fighter can gain on the night of the fight, which could lead to financial penalties.
Kal Sajad is a reporter for the British Broadcasting Corporation.
It all feels a bit strange.
The idea of a Eubank Jr v Benn fight was just a fantasy until a few weeks ago.
They were both legends in the sport. The winner of the first fight told the interviewer he was in too much pain to speak. Two men went to fight. It was done twice. They'll have a lot to live up to.
It is a fight which makes sense and has all the potential to pull in the casual sports fans, as both boxers have created a fanbase in their own right, but are also tapping into thelegacy and support of their legendary fathers.
The build-up to their Eubank Jr-Benn may be a little forced or orchestrated at times, but they are far from camera shy or hesitant to speak their minds.
Two fighters are fighting in the ring. He has the ability to finish off an opponent with a flurry of punches and he will treat you to flashy combinations. Benn is one of the most improved British fighters in the sport and he fights with real intensity.
With his experience and weight advantage, Eubank Jr. will be the favorite. Many feel that he has failed as a professional. He has a lot to gain. His career would take off if he beat the bigger man.