| Champ: |  Petra Kvitová |
| Runner: |  Garbiñe Muguruza |
| Score: | 6–2, 6–1 |
| Draw: | 28 |
| Seeds: | 8 |
| Type: | singles doubles |
| Before Name: | Qatar Total Open |
See main article: 2021 Qatar Total Open.
Petra Kvitová defeated Garbiñe Muguruza in the final, 6–2, 6–1 to win the singles tennis title at the 2021 WTA Qatar Open. The final was a rematch of the 2018 final. It was Kvitová's second title at the WTA Qatar Open. Kvitová dropped just one set the entire tournament, to Anett Kontaveit in the quarterfinals.
Aryna Sabalenka was the defending champion,[1] [2] but lost in the second round to Muguruza.
The top four seeds received a bye into the second round.
