Potito Starace is the defending champion. Starace lost in the final against Simone Bolelli 6–7(7–9), 2–6.
Feliciano López won last year's edition, but decided not to participate this year.
Daniel Gimeno-Traver defeated Adrian Mannarino 6–4, 7–6(2) in the final.
Daniel Gimeno-Traver won last year's edition, but decided not to participate this year.
Top seed Marcel Granollers won in the final match and became the new champion. He defeated Jaroslav Pospíšil 1–6, 7–5, 6–0.
Martín Vassallo Argüello chose to not defend his 2008 title.
Ramón Delgado won the tournament in his own country, after defeating Daniel Gimeno-Traver 7–6(2), 1–6, 6–3 in the final.
This was the first edition of the tournament.
Olivier Rochus won the final 6–2, 6–3 against Stéphane Robert.
Sergiy Stakhovsky was the defending champion but chose to compete in the 2011 Aegon International.
The 2012 Monte-Carlo Rolex Masters was a tennis tournament played at the Monte Carlo Country Club, in Roquebrune-Cap-Martin, France, near Monte Carlo, Monaco. The tournament was part of the 2012 ATP World Tour and was played on outdoor clay courts. Rafael Nadal was the seven-time defending champion of the singles event having won this event in 2011 and successfully defended his title by beating Novak Djokovic 6–3, 6–1 in the final. Nadal's victory was his eighth consecutive Monte-Carlo Masters singles title, having won this event in the past from 2005 to 2011. Nadal became the first man in the open era to win a tournament eight consecutive times.
Andreas Haider-Maurer was the defending champion but decided not to participate.
Tommy Robredo won the title by defeating Gastão Elias 6–3, 6–2 in the final.
Julian Reister was the defending champion.
Daniel Gimeno-Traver won the final after defeating Albert Montañés 6–2, 4–6, 6–4 in the final.
Daniel Gimeno-Traver successfully defended his title, defeating Tommy Robredo 6–3, 6–2 in the final.
Thiemo de Bakker was the defending champion, but lost in the semifinals to Daniel Gimeno-Traver.
Daniel Gimeno-Traver won the title for the third year in a row, defeating Stéphane Robert 6–4, 7–6(7–2)
Stanislas Wawrinka was the defending champion, but withdrew before the event started.
Carlos Berlocq won the title, defeating Tomáš Berdych in the final, 0–6, 7–5, 6–1.
Rafael Nadal was the defending champion, but lost in the semifinals to Fabio Fognini.
Rafael Nadal was the two-time defending champion, but lost to Andy Murray in the final, 3–6, 2–6.
David Ferrer was the defending champion, but lost in the quarterfinals to Dominic Thiem.
Novak Djokovic was the defending champion, but lost in the second round to Jiří Veselý.
Philipp Kohlschreiber was the defending champion, but lost in the second round to Karen Khachanov.
Richard Gasquet was the defending champion, but did not compete in the juniors that year.
Todd Reid was the defending champion, but did not complete in the Juniors this year.
