Jinh Yu Frey (nee Jinh Hie Yu)  is an American mixed martial artist and currently competes in the strawweight division of the Ultimate Fighting Championship. She was born in Crossett, Arkansas and raised in Amarillo, Texas. Frey's father died when she was a teenager, which she did not discover until she was 20 years old due to her mentally ill mother's unreliable narration. Frey's father was a Taekwondo instructor and and her mother and brother also trained Taekwondo. Frey was the odd one out in the family, choosing volleyball, softball, and track and field over martial arts. Frey graduated from Palo Duro High School in three years and her GPA put her in the Top 2% in her class. She earned an associate's degree in Nuclear Medicine at Amarillo College, a Bachelor of Science in Radiologic Sciences from Midwestern State University, and a Masters Degree in Business Administration from the University of Texas at Arlington. Frey also earned Summa Cum Laude honors at all three higher education institutions. Frey began training mixed martial arts at age 22.  Frey moved to the Dallas-Fort Worth area after marrying Douglas Frey (who has a background in wrestling and went 10-13 in his MMA career) and trains at Fortis MMA. She trained at Mohler MMA prior to 2021. She is a purple belt in Brazilian jiu-jistu.

Frey had a brief amateur career before making her professional MMA debut in 2013. She won her first fight against Meghan Harris via first round rear naked choke (Sugar Creek Showdown 16: Resolution). In her second professional fight, Frey knocked out Darla Harris with a head kick and a straight left that went viral on YouTube (Sugar Creek Showdown 18: Declaration of Pain). Frey capitalized on this kncokout and made her Invicta FC debut at Invicta FC 8: Waterson vs. Tamada. She would lose to Jodie Esquibel via split decision. Frey would win her next three fights in Invicta, defeating Cassie Robb by rear naked choke (Invicta FC 10: Waterson vs. Tiburcio) and defeating Liz McCarthy (Invicta FC 14: Evinger vs. Kianzad) and Herica Tiburcio (Invicta FC 16: Hamasaki vs. Brown) via unanimous decision. This earned her a title shot against Ayaka Hamasaki at Invicta FC 19: Maia vs. Modafferi. Frey would lose in the second round via doctor stoppage.

Frey picked up a unanimous decision win over Ashley Cummins (Invicta FC 24: Dudieva vs. Borella) and earned another title shot against Minna Grusander at Invicta FC 30 on July 21, 2018. Frey defeated Grusander and won the vacant Invicta FC Atomweight Championship. However, many observers thought Grusander won the fight. As a result the two had a rematch at Invicta FC 33 on December 15, 2018. Frey won the rematch via split decision and defended her Atomweight title. Frey tried and failed to take the Rizin Super Atomweight Championship off of Hamasaki (Rizin 16) before missing weight and being stripped of her Invicta title before her second fight with Cummins (Invicta FC 39: Frey vs. Cummins II). Nevertheless, Frey defeated Cummins once again via unanimous decision.

Frey moved up to Strawwweight to make her UFC debut against Kay Hansen (UFC on ESPN: Poirier vs. Hooker), losing via armbar in the third round. Frey dropped a unanimous decision to Loma Lookbonmee (UFC on ESPN: Holm vs. Aldana) before picking up back to back decision wins over Gloria de Paula (UFC Fight Night: Edwards vs. Muhammad) and Ashley Yoder (UFC on ESPN: Hall vs. Strickland). Frey's most recent fight was against Vanessa Demopoulos at UFC on ESPN: Tsarukyan vs. Gamrot. The fight was fairly close, with Frey dominating the striking exchanges and Demopoulos gaining the edge in the grappling exchanges. Sal D'Amato gave Frey the nod with a 29-28 scorecard, while Ron McCarthy gave Demopoulos a 29-28 and Jerin Valel gave Demopoulos a 30-27. Frey's loss was somewhat controversial, with most observers scoring the fight in her favor. As of 9/8/2022, Frey is scheduled to face Polyana Viana on November 5, 2022.