| Singles | |
|---|---|
| 2021 Open Ciudad de Valencia | |
| Champion |  Arantxa Rus |
| Runner-up |  Mihaela Buzărnescu |
| Final score | 6–4, 7–6(7–3) |
Varvara Gracheva was the defending champion [1] but chose to participate at the 2021 J&T Banka Ostrava Open instead.
Arantxa Rus won the title, defeating Mihaela Buzărnescu in the final, 6–4, 7–6(7–3).
Arantxa Rus (Champion)
Martina Trevisan (Withdrew) Sara Errani (Withdrew) Irina Bara (Quarterfinals)
Kristína Kučová (First round)
Dalma Gálfi (First round, retired)
Ekaterine Gorgodze (First round)
Francesca Jones (Quarterfinals)
Aliona Bolsova (Semifinals)| Semifinals | Final | ||||||||||||
| 1 | Arantxa Rus | 77 | 6 | ||||||||||
 Seone Mendez | 63 | 2 | |||||||||||
| 1 | Arantxa Rus | 6 | 77 | ||||||||||
| Mihaela Buzărnescu | 4 | 63 | |||||||||||
| Mihaela Buzărnescu | 6 | 6 | |||||||||||
| 9 | Aliona Bolsova | 4 | 2 | ||||||||||
| First Round | Second Round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 1 | A Rus | 6 | 6 | ||||||||||||||||||||||||
| Q | IG Ghioroaie | 3 | 1 | 1 | A Rus | 6 | 6 | ||||||||||||||||||||
 V Cepede Royg | 3 | 77 | 2 | Q |  I Shymanovich | 3 | 4 | ||||||||||||||||||||
| Q | I Shymanovich | 6 | 64 | 6 | 1 | A Rus | 6 | 6 | |||||||||||||||||||
| WC | Á Fita Boluda | 6 | 6 |  D Seguel | 4 | 1 | |||||||||||||||||||||
| WC | R Masarova | 1 | 3 | WC | Á Fita Boluda | 4 | 77 | 1 | |||||||||||||||||||
| D Seguel | 6 | 64 | 6 | D Seguel | 6 | 61 | 6 | ||||||||||||||||||||
| 7 | E Gorgodze | 4 | 77 | 2 | 1 | A Rus | 77 | 6 | |||||||||||||||||||
| 4 | I Bara | 6 | 6 | S Mendez | 63 | 2 | |||||||||||||||||||||
| LL | A Carreras | 4 | 3 | 4 | I Bara | 4 | 6 | 6 | |||||||||||||||||||
 C Paquet | 6 | 77 | C Paquet | 6 | 4 | 4 | |||||||||||||||||||||
| I Burillo Escorihuela | 1 | 65 | 4 | I Bara | 3 | 710 | 4 | ||||||||||||||||||||
| S Mendez | 6 | 6 | S Mendez | 6 | 68 | 6 | |||||||||||||||||||||
 S Waltert | 3 | 0 | S Mendez | 6 | 6 | ||||||||||||||||||||||
| Q | L Romero Gormaz | 3 | Q | L Romero Gormaz | 0 | 2 | |||||||||||||||||||||
| 6 | D Gálfi | 1r | |||||||||||||||||||||||||
| First Round | Second Round | Quarterfinals | Semifinals | ||||||||||||||||||||||||
| 5 | K Kučová | 77 | 3 | 3 | |||||||||||||||||||||||
| Q | A Prisăcariu | 64 | 6 | 6 | Q | A Prisăcariu | 0 | 1 | |||||||||||||||||||
 P Ormaechea | 3 | 63 | M Buzărnescu | 6 | 6 | ||||||||||||||||||||||
| M Buzărnescu | 6 | 77 | M Buzărnescu | 6 | 6 | ||||||||||||||||||||||
| WC |  A Gámiz | 4 | 711 | 77 | WC | A Gámiz | 2 | 3 | |||||||||||||||||||
| Q | M Bassols Ribera | 6 | 69 | 64 | WC | A Gámiz | 7 | 7 | |||||||||||||||||||
| WC | J Bouzas Maneiro | 2 | 2 | LL | E Guerrero Álvarez | 5 | 5 | ||||||||||||||||||||
| LL | E Guerrero Álvarez | 6 | 6 | M Buzărnescu | 6 | 6 | |||||||||||||||||||||
| 8 | F Jones | 6 | 6 | 9 | A Bolsova | 4 | 2 | ||||||||||||||||||||
| Q | N Bains | 3 | 1 | 8 | F Jones | 78 | 6 | ||||||||||||||||||||
| JE | D Parry | 3 | 3 |  D Papamichail | 66 | 1 | |||||||||||||||||||||
| D Papamichail | 6 | 6 | 8 | F Jones | 64 | 1 | |||||||||||||||||||||
| Q | M Gutiérrez Carrasco | 6 | 0 | 6 | 9 | A Bolsova | 77 | 6 | |||||||||||||||||||
 Ç Büyükakçay | 2 | 6 | 4 | Q | M Gutiérrez Carrasco | 77 | 4 | 0 | |||||||||||||||||||
| Q |  F Kozaki | 2 | 2 | 9 | A Bolsova | 65 | 6 | 6 | |||||||||||||||||||
| 9 | A Bolsova | 6 | 6 | ||||||||||||||||||||||||
Kristína Kučová was the defending champion, but did not compete in the juniors that year.
Kaia Kanepi was the defending champion but chose not to compete.
Anastasia Pivovarova defeated Arantxa Rus in the final 7–6(7–4), 6–7(3–7), 6–2.
Ana Ivanovic was the defending champion, but decided not to participate.
Anabel Medina Garrigues was the defending champion, but lost in the second round to Silvia Soler Espinosa.
Caroline Wozniacki was the defending champion, but she chose not to participate.
Agnieszka Radwańska won the title, defeating Simona Halep 7–5, 6–0 in the final.
Serena Williams was the defending champion, but chose not to compete this year.
Mona Barthel was the defending champion, but she lost to Johanna Larsson in the final, 3–6, 6–7(2–7).
Ons Jabeur was the defending champion, but chose not to participate.
Simona Halep was the defending champion, but chose not to participate this year.
Laura Siegemund was the defending champion, but could not defend her title due to a right knee injury.
Lesia Tsurenko was the defending champion and successfully defended her title, defeating Stefanie Vögele in the final, 5–7, 7–6(7–2), 6–2.
Karolína Plíšková was the defending champion, but lost in the quarterfinals to Aryna Sabalenka.
Maryna Zanevska was the defending champion, but lost to Nao Hibino in the second round.
Barbora Strýcová was the defending champion, but lost in the quarterfinals to Alison Van Uytvanck.
Carina Witthöft was the defending champion, but lost in the first round to Vera Lapko.
Belinda Bencic was the champion the last time the event was held in 2017, but chose to compete in St. Petersburg instead.
Tatjana Maria was the defending champion, but chose not to participate this year.
Rebecca Šramková was the defending champion but lost in the quarterfinals to Natalia Vikhlyantseva.
Laura Ioana Paar and Julia Wachaczyk were the defending champions but lost in the quarterfinals to Viktória Kužmová and Arantxa Rus.
Arantxa Rus and Tamara Zidanšek were the reigning champions, but chose not to participate.