The 115-pound title fight will take place on the pay-per-view portion of UFC 205 but will not headline the event, which is scheduled to take place at Madison Square Garden.
Jedrzejczyk (12-0) will be seeking her fourth title defense. The Polish strawweight has dominated the Octagon since her UFC debut in 2014. Her closest fight during that time was a split decision in 2015 against Claudia Gadelha, whom she went on to defeat again this July.
She'll face a fellow Poland native in Kowalkiewicz (10-0), who is coming off a split decision win against Rose Namajunas at UFC 201 in July.
The UFC has yet to announce a main event for UFC 205. The event will be historic in that it marks the promotion's first trip to New York since a 1997 ban on professional mixed martial arts was lifted earlier this year.