Unai Marrero Larrañaga (born 9 October 2001) is a Spanish professional footballer who plays as a goalkeeper for Real Sociedad.

Born in San Sebastián, Gipuzkoa, Basque Country, Marrero joined Real Sociedad's youth setup in 2016, from CD Lagun Onak.

[1] He made his senior debut with the C-team on 14 September 2019, starting in a 1–2 Tercera División away loss against Pasaia KE.

[2] Marrero made his professional debut with the reserves on 10 October 2021, coming on as a first-half substitute for outfield player Jon Karrikaburu as Andoni Zubiaurre was sent off in a 1–1 home draw against SD Ponferradina in the Segunda División.

[3] He was definitely promoted to the B's ahead of the 2022–23 Primera Federación, and renewed his contract until 2027 on 12 July 2023.