Johnathan Nieves (born June 1, 1997) is an American actor. He is best known for playing Mateo Vega in Penny Dreadful: City of Angels (2020), and Richie Valdovinos in the musical TV series Grease: Rise of the Pink Ladies in 2023.

Nieves was born and raised in Chicago, Illinois, U.S. He studied improv at The Second City Conservatory and the Chicago Actors Studio.

In 2015, Nieves made his screen debut in an episode of Chicago Fire, followed in 2016 with an appearance in an episode of Shameless. In 2018, he guest-starred as Javier Pagan in New Amsterdam, and as David in season 4 of Better Call Saul, alongside Bob Odenkirk and Jonathan Banks.
In 2019, he starred as Eduardo in the Stefon Bristol directed sci-fi film See You Yesterday, in a cast which included Michael J. Fox and the rapper Astro. The same year he played Hunter Martinez in an episode of the medical series Grey’s Anatomy.

In 2020, he secured a main role, playing Mateo Vega in the American historical dark fantasy television series Penny Dreadful: City of Angels, working alongside Natalie Dormer and Rory Kinnear.

In 2023, Nieves played the main role of Richie Valdovinos brother of Olivia, and leader of the gang ‘T-Birds’, in the Paramount+ American musical romantic comedy television series Grease: Rise of the Pink Ladies, which is a prequel to the 1978 film Grease.

Theatrical performances include: