| William Mendieta | |
| Fullname: | William Gabriel Mendieta Pintos |
| Birth Date: | 9 January 1989 |
| Birth Place: | Asunción, Paraguay |
| Height: | 1.74 m |
| Position: | Attacking midfielder |
| Currentclub: | Libertad |
| Clubnumber: | 16 |
| Youthclubs1: | Libertad |
| Years1: | 2009–2013 |
| Caps1: | 40 |
| Goals1: | 11 |
| Years2: | 2011 |
| Clubs2: | → Rubio Ñu (loan) |
| Caps2: | 17 |
| Goals2: | 1 |
| Years3: | 2012 |
| Clubs3: | → Sol de América (loan) |
| Caps3: | 17 |
| Goals3: | 1 |
| Years4: | 2013–2016 |
| Clubs4: | Palmeiras |
| Caps4: | 28 |
| Goals4: | 4 |
| Years5: | 2015–2016 |
| Clubs5: | → Olimpia (loan) |
| Caps5: | 59 |
| Goals5: | 26 |
| Years6: | 2017–2021 |
| Clubs6: | Olimpia |
| Caps6: | 56 |
| Goals6: | 25 |
| Years7: | 2020–2021 |
| Clubs7: | → FC Juárez (loan) |
| Caps7: | 19 |
| Goals7: | 1 |
| Years8: | 2021– |
| Clubs8: | Libertad |
| Caps8: | 56 |
| Goals8: | 25 |
| Nationalyears1: | 2012–2018 |
| Nationalteam1: | Paraguay |
| Nationalcaps1: | 2 |
| Nationalgoals1: | 0 |
| Club-Update: | 00:00, 1 March 2022 (UTC) |
William Mendieta (born 9 January 1989) is a Paraguayan international footballer who plays for Club Libertad as an attacking midfielder or winger.
Born in Asunción, Mendieta has played for Libertad, Rubio Ñu and Sol de América.
In 2013, Mendieta completed a transfer to Palmeiras for around U$$2 Million.
Mendieta made his international debut for Paraguay in 2012.