The bout will be televised and live streamed online in the United Kingdom and Ireland on BoxNation.
Golovkin looks to defend his championship for a record-tying 20th consecutive time against Martirosyan.
A lovely combo sent his opponent crashing to the canvas, bringing his record to a stellar 38-0-1 (34 KO's).
The rematch seemed inevitable, and it might have been the biggest fight of the year - until Canelo failed a doping test in February.
Golovkin stopped Martirosyan at round at 1:53 in round 2 becoming the first person to ever knockout the sturdy former US Olympian.
Martirosyan, who normally fights at light middleweight, will be stepping up a division to face the hard-hitting Golovkin, who is unbeaten through 38 fights, including 33 by knockout.
Cardenal australiano George Pell va a juicio por acusaciones de abuso
Más de 30 testigos presentaron sus declaraciones durante las audiencias preliminares que se desarrollaron durante cuatro semanas. A partir de esta situación, el australiano se declaró "no culpable" ante la justicia de su país.
The fight was arranged at the last minute after Golovkin's rematch with Canelo Alavarez fell apart.
Golovkin said after the fight he would take on all comers, including Alvarez.
Now, Golovkin will potentially revisit a faceoff with Canelo Alvarez, with Alvarez able to fight by September following his suspension for Clenbuterol. I finally get a guy that wants to fight and come forward. "I've been killing myself for the last two years, just thinking, 'What mistakes did I make, or what did I do to deserve this, to be inactive outside of the ring?' This fight is everything I've dreamed of, and I can't wait to show it to the world". The Nevada state athletic commission, which had jurisdiction over the contest, suspended Alvarez until 17 August, clearing the way for a September rematch.
"I feel very happy that it's all been resolved and I'm going to be fighting in a very important fight where several belts will be at stake and I think the audience will enjoy it". The IBF's reasoning was that Martirosyan is a junior middleweight moving up in weight who has not fought in two years with that fight being a loss.
Golovkin's trainer Abel Sanchez is in agreement and believes there are plenty of other fighters who deserve the chance to face him such as World Boxing Organization champion Billy Joe Saunders, Jermall Charlo and Sergey Derevyanchenko among others.