Pedro Tonon Geromel is a Brazilian professional footballer who plays for Gremio Foot-Ball Porto Alegrense as a central defender.

At Guimaraes, after making his debut in a 0–2 derby home loss against S.C. Braga, he eventually became an undisputed first-choice, as the Minho team promoted from the second level and achieved qualification to the UEFA Champions League in just two seasons. In an online voting, Geromel was considered as 2007–08's best player in the Portuguese League. On 30 June 2008 he moved to Bundesliga side 1. FC Koln, recently promoted to the top division. On 23 August 2012, Geromel signed a four-year loan deal with RCD Mallorca in Spain. In his first season he contributed with 29 starts and one goal (2,612 minutes of action), but the Balearic Islands club was relegated from the top flight; in December 2013 he rescinded his agreement and returned to his country, to sign for two years and a half with Gremio Foot-Ball Porto Alegrense while still owned by Koln.

On 27 August 2016, Geromel was called up for the Brazil national team by coach Tite, replacing the injured Rodrigo Caio. His first cap arrived the following 25 January, when he played the full 90 minutes in a 1–0 friendly win over Colombia at the Estadio Olimpico Nilton Santos. In May 2018, Geromel was selected for FIFA World Cup in Russia.