| 2026-09-26 | UFC Fight Night: Rosas Jr. vs. Barcelos | Women’s Strawweight | Yazmin Jauregui def. Vanessa Demopoulos | KO (punches) | 1 | 1:02 |
| 2025-06-14 | UFC on ESPN: Usman vs. Buckley | Women’s Flyweight | Jamey-Lyn Horth def. Vanessa Demopoulos | Decision (unanimous) (30–27, 30–27, 30–27) | 3 | 5:00 |
| 2025-04-05 | UFC on ESPN: Emmett vs. Murphy | Women’s Strawweight | Talita Alencar def. Vanessa Demopoulos | Decision (unanimous) (30–26, 30–27, 30–27) | 3 | 5:00 |
| 2024-09-07 | UFC Fight Night: Burns vs. Brady | Women’s Strawweight | Jaqueline Amorim def. Vanessa Demopoulos | Submission (armbar) | 1 | 3:28 |
| 2024-05-18 | UFC Fight Night: Barboza vs. Murphy | Women’s Strawweight | Vanessa Demopoulos def. Emily Ducote | Decision (split) (28–29, 29–28, 29–28) | 3 | 5:00 |
| 2023-10-07 | UFC Fight Night: Dawson vs. Green | Women’s Strawweight | Vanessa Demopoulos def. Kanako Murata | Decision (unanimous) (29–28, 29–28, 29–28) | 3 | 5:00 |
| 2023-05-20 | UFC Fight Night: Dern vs. Hill | Catchweight | Karolina Kowalkiewicz def. Vanessa Demopoulos | Decision (unanimous) (30–27, 30–27, 30–27) | 3 | 5:00 |
| 2022-11-19 | UFC Fight Night: Nzechukwu vs. Cuțelaba | Women’s Strawweight | Vanessa Demopoulos def. Maria Oliveira | Decision (unanimous) (29–28, 29–28, 29–28) | 3 | 5:00 |
| 2022-06-25 | UFC on ESPN: Tsarukyan vs. Gamrot | Women’s Strawweight | Vanessa Demopoulos def. Jinh Yu Frey | Decision (split) (28–29, 29–28, 30–27) | 3 | 5:00 |
| 2022-01-22 | UFC 270: Ngannou vs. Gane | Women’s Strawweight | Vanessa Demopoulos def. Silvana Gómez Juárez | Submission (armbar) | 1 | 2:25 |
| 2021-08-28 | UFC on ESPN: Barboza vs. Chikadze | Women’s Flyweight | JJ Aldrich def. Vanessa Demopoulos | Decision (unanimous) (30–27, 30–27, 30–27) | 3 | 5:00 |