Julianna Peña has six losses against six opponents on her MMA record. For a list of Peña's best fights, refer to "Best fights of Julianna Peña".
On June 7, 2025 Julianna Peña met Kayla Harrison in a bantamweight (UFC Women's Championship) title defense fight. Peña was 35 years old and with a record of 12-6 (8), and Harrison was 34 years old and with a record of 18-1 (13). Peña lost the fight via 2nd-round submission and lost the title.
On July 30, 2022 Julianna Peña met Amanda Nunes in a bantamweight (UFC Women's Championship) title defense fight. Peña was 32 years old and with a record of 11-5 (8), and Nunes was 34 years old and with a record of 21-5 (16). Peña lost the fight via 5-round unanimous decision and lost the title.
On October 4, 2020 Julianna Peña faced off against Germaine de Randamie in a bantamweight bout at age 31. She was coming in with a record of 9-4 (6), and Randamie was 36 years old and with a record of 9-4 (4). Peña lost the fight via 3rd-round choke-out.
On January 28, 2017 Julianna Peña faced off against Valentina Shevchenko in a bantamweight bout at age 27. She was coming in with a record of 8-3 (6), and Shevchenko was 28 years old and with a record of 13-2 (9). Peña lost the fight via 2nd-round submission.
On February 8, 2013 Julianna Peña faced off against DeAnna Bennett in a flyweight bout at age 23. She was coming in with a record of 4-2 (4), and Bennett was 28 years old and with a record of 1-0 (1). Peña lost the fight via 3-round unanimous decision.
On April 19, 2012 Julianna Peña faced off against Sarah Moras in a bantamweight bout at age 22. She was coming in with a record of 4-1 (4), and Moras was 23 years old and with a record of 1-0 (1). Peña lost the fight via 2nd-round TKO.
