Álvaro Guillén Meza (born 2 January 2003) is an Ecuadorian tennis player. He has a career high ATP singles ranking of world No. 215 achieved on 12 August 2024 and a doubles ranking of No. 400 achieved on 22 July 2024. He is currently the No. 2 Ecuadorian tennis player.
Guillén Meza represents Ecuador at the Davis Cup, where he has a W/L record of 1–1.
At 20 years old, he became the youngest Ecuadorian champion since Giovanni Lapentti in 2003 after winning the 2023 Lima Challenger.