Tate, the UFC's second-ranked female fighter in the 135-pound division, is scheduled to fight Rin Nakai on Sept. 20 in Tokyo.
She's also the second UFC fighter to join Harvick's athlete-representation company. Harvick's group already includes fighter Donald "Cowboy" Cerrone.
Cerrone fights fellow 155-pound standout Bobby "King" Green in the co-main event of UFC 178 on Sept. 27 in Las Vegas.
Tate was a coach on "The Ultimate Fighter: Team Rousey vs. Team Tate" in 2013. Tate is 14-5 but has lost twice to Ronda Rousey.
"Everyone's really close-knit and I can tell it's going to be a great working atmosphere," Tate said.
Tate, a former Strikeforce Women's bantamweight champion, is based and trains in Las Vegas. The 27-year-old made her UFC debut in April 2013, taking on Cat Zingano in "The Ultimate Fighter 17" finale, which marked the second women's MMA matchup in the UFC.
KHI Management and Tate agreed to a multiyear deal.
"We wanted to represent one of the top names in UFC," Harvick said. "We wanted a female athlete to kind of fit in a group of athletes and artists that we currently have in the KHI Management family."
Like Rousey, perhaps UFC's biggest star, Tate wants to expand her career outside of the cage. She appeared in the ESPN The Magazine's Body Issue in 2013 and would like to see her career blossom in other areas of entertainment.
"I want to branch out beyond MMA," she said.
There's at least one route for MMA-NASCAR cross promotion: NASCAR and UFC both have TV deals with Fox.
"UFC has a younger demographic," Harvick said. "NASCAR doesn't have quite the reach UFC does. It took us a little bit to figure out exactly how we wanted to activate sponsors at a UFC fight. But in the last three fights, we've kind of taken a different approach and we've had great participation from all the sponsors we've entertained."
Harvick leaves the bulk of the business side of KHI to his wife, DeLana, and director of business development Josh Jones. Harvick said his wife urged him to target an elite female athlete.
"She was the first one to say you better make this happen," Harvick said.
Tate also credits a significant other for striking the deal -- boyfriend and fellow UFC fighter Bryan Caraway urged her to seek out KHI.
"It's the best thing I've done, I think, in my career," Tate said