| Guilherme Costa | |
| Fullname: | Guilherme Costa Machado Silveira |
| Birth Date: | 31 March 1994 |
| Birth Place: | Rio de Janeiro, Brazil |
| Height: | 1.78 m |
| Position: | Attacking midfielder, Winger |
| Youthyears1: | 2006–2014 |
| Youthclubs1: | Vasco da Gama |
| Years1: | 2012–2021 |
| Clubs1: | Vasco da Gama |
| Caps1: | 24 |
| Goals1: | 2 |
| Years2: | 2015 |
| Clubs2: | → Bragantino (loan) |
| Caps2: | 5 |
| Goals2: | 0 |
| Years3: | 2016 |
| Clubs3: | → Boavista (loan) |
| Caps3: | 13 |
| Goals3: | 2 |
| Years4: | 2018 |
| Clubs4: | → Vitória (loan) |
| Caps4: | 16 |
| Goals4: | 1 |
| Years5: | 2019 |
| Clubs5: | → CRB (loan) |
| Caps5: | 6 |
| Goals5: | 0 |
| Years6: | 2020 |
| Clubs6: | → Boavista (loan) |
| Caps6: | 3 |
| Goals6: | 0 |
| Nationalyears1: | 2008–2009 |
| Nationalteam1: | Brazil U15 |
| Nationalyears2: | 2010–2011 |
| Nationalteam2: | Brazil U17 |
| Pcupdate: | 02 January 2019 (UTC) |
Guilherme Costa Machado Silveira (born 31 March 1994), commonly known as Guilherme Costa or Guilherme, is a Brazilian footballer who plays as an attacking midfielder.