The event takes place on June 8 at Ergo Arena in Gdansk/Sopot, Poland.
The match features two of the top finishers in the division. Manhoef has stopped opponents in all of his wins, with 25 career knockouts and two submissions, while Khalidov has 11 KO's, 14 submissions and only one decision among his 26 victories.
Khalidov has only lost once since Oct. 2005, a span over 26 bouts. He holds wins over former or current UFC fighters Jorge Santiago, Igor Pokrajac, Rodney Wallace, James Irvin, Matt Lindland and Kendall Grove.
He's won each of his last five fights by stoppage, including a submission win over Grove in his most recent bout. He has in the past been offered a UFC deal but passed, saying he made more money fighting in KSW.
Meanwhile, his opponent Manhoef has chased a UFC deal, but has not been able to secure one. His campaign was set back in his most recent performance, a decision loss to Brock Larson at ONE FC 8. That defeat snapped a three-fight win streak for the 36-year-old, who has a career record of 27-10-1 with 1 no contest.