| 2025-10-11 | UFC Fight Night: Oliveira vs. Gamrot | Women’s Strawweight | Julia Polastri def. Karolina Kowalkiewicz | TKO (head kick and punches) | 3 | 2:56 |
| 2024-11-09 | UFC Fight Night: Magny vs. Prates | Women’s Strawweight | Denise Gomes def. Karolina Kowalkiewicz | Decision (unanimous) (30–27, 30–27, 29–28) | 3 | 5:00 |
| 2024-05-04 | UFC 301: Pantoja vs. Erceg | Women’s Strawweight | Iasmin Lucindo def. Karolina Kowalkiewicz | Decision (unanimous) (30–27, 30–27, 30–27) | 3 | 5:00 |
| 2023-10-07 | UFC Fight Night: Dawson vs. Green | Women’s Strawweight | Karolina Kowalkiewicz def. Diana Belbiţă | Decision (unanimous) (30–27, 30–27, 30–27) | 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 |
| 2022-11-12 | UFC 281: Adesanya vs. Pereira | Women’s Strawweight | Karolina Kowalkiewicz def. Silvana Gómez Juárez | Decision (unanimous) (29–28, 29–28, 29–28) | 3 | 5:00 |
| 2022-06-04 | UFC Fight Night: Volkov vs. Rozenstruik | Women’s Strawweight | Karolina Kowalkiewicz def. Felice Herrig | Submission (rear-naked choke) | 2 | 4:01 |
| 2021-08-07 | UFC 265: Lewis vs. Gane | Women’s Strawweight | Jessica Penne def. Karolina Kowalkiewicz | Submission (armbar) | 1 | 4:32 |
| 2020-02-23 | UFC Fight Night: Felder vs. Hooker | Women’s Strawweight | Yan Xiaonan def. Karolina Kowalkiewicz | Decision (unanimous) (30–26, 30–26, 30–26) | 3 | 5:00 |
| 2019-06-08 | UFC 238: Cejudo vs. Moraes | Women’s Strawweight | Alexa Grasso def. Karolina Kowalkiewicz | Decision (unanimous) (30–27, 30–27, 30–27) | 3 | 5:00 |
| 2019-03-30 | UFC on ESPN: Barboza vs. Gaethje | Women’s Strawweight | Michelle Waterson def. Karolina Kowalkiewicz | Decision (unanimous) (30–27, 30–27, 30–27) | 3 | 5:00 |
| 2018-09-08 | UFC 228: Woodley vs. Till | Women’s Strawweight | Jéssica Andrade def. Karolina Kowalkiewicz | KO (punch) | 1 | 1:58 |
| 2018-04-07 | UFC 223: Khabib vs. Iaquinta | Women’s Strawweight | Karolina Kowalkiewicz def. Felice Herrig | Decision (split) (29–28, 28–29, 29–28) | 3 | 5:00 |
| 2017-10-21 | UFC Fight Night: Cowboy vs. Till | Women’s Strawweight | Karolina Kowalkiewicz def. Jodie Esquibel | Decision (unanimous) (30–27, 30–27, 30–27) | 3 | 5:00 |
| 2017-06-03 | UFC 212: Aldo vs. Holloway | Women’s Strawweight | Cláudia Gadelha def. Karolina Kowalkiewicz | Submission (rear-naked choke) | 1 | 3:03 |
| 2016-11-12 | UFC 205: Alvarez vs. McGregor | Women’s Strawweight | Joanna Jędrzejczyk def. Karolina Kowalkiewicz title | Decision (unanimous) (49–46, 49–46, 49–46) | 5 | 5:00 |
| 2016-07-30 | UFC 201: Lawler vs. Woodley | Women’s Strawweight | Karolina Kowalkiewicz def. Rose Namajunas | Decision (split) (28–29, 29–28, 29–28) | 3 | 5:00 |
| 2016-05-08 | UFC Fight Night: Overeem vs. Arlovski | Women’s Strawweight | Karolina Kowalkiewicz def. Heather Jo Clark | Decision (unanimous) (29–28, 29–28, 30–27) | 3 | 5:00 |
| 2015-12-19 | UFC on Fox: dos Anjos vs. Cowboy 2 | Women’s Strawweight | Karolina Kowalkiewicz def. Randa Markos | Decision (unanimous) (29–28, 29–28, 30–27) | 3 | 5:00 |