2021 WTA Finals – Doubles
| Doubles | |
|---|---|
| 2021 WTA Finals | |
| Champions | Barbora Krejčíková Kateřina Siniaková |
| Runners-up | Hsieh Su-wei Elise Mertens |
| Score | 6–3, 6–4 |
| Draw | 8 (round robin) |
Barbora Krejčíková and Kateřina Siniaková defeated Hsieh Su-wei and Elise Mertens in the final, 6–3, 6–4 to win the doubles tennis title at the 2021 WTA Finals.
Tímea Babos and Kristina Mladenovic were the two-time reigning champions, but failed to qualify this year.
Krejčíková and Siniaková clinched the year-end no. 1 as a team with their win against Sharon Fichman and Giuliana Olmos in their first round-robin match, and Siniaková secured the individual year-end no. 1 ranking by winning the title. Hsieh was also in contention for the top ranking. Krejčíková was the only player in this edition to qualify for both the singles and doubles tournaments.