The 2012 ATP Vegeta Croatia Open Umag was a men's tennis tournament played on outdoor clay courts. It was the 23rd edition of the ATP Vegeta Croatia Open Umag, and was part of the ATP World Tour 250 Series of the 2012 ATP World Tour. It took place at the International Tennis Center in Umag, Croatia, from 9 July until 15 July 2012. Marin Čilić won the singles title.
| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
 Spain | Fernando Verdasco[1] | 16 | 1 | |
| Marin Čilić[2] | 18 | 2 | ||
 Ukraine | Alexandr Dolgopolov | 21 | 3 | |
| Spain | Marcel Granollers | 23 | 4 | |
 Argentina | Carlos Berlocq | 37 | 5 | |
| Spain | Juan Carlos Ferrero | 38 | 6 | |
 Slovakia | Martin Kližan | 62 | 7 | |
 France | Édouard Roger-Vasselin | 67 | 8 |
The following players received wildcards into the singles main draw:
The following players received entry from the qualifying draw:
Richard Gasquet (fatigue)| Country | Player | Country | Player | Rank1 | Seed | |
|---|---|---|---|---|---|---|
| Spain | Marcel Granollers | Spain | Marc López | 35 | 1 | |
| Daniele Bracciali | Fabio Fognini | 65 | 2 | |||
| Spain | David Marrero | Fernando Verdasco | 89 | 3 | ||
| France |
The following pairs received wildcards into the doubles main draw:
The following pairs received entry as alternates:
See main article: 2012 ATP Vegeta Croatia Open Umag – Singles. Marin Čilić defeated Marcel Granollers, 6–4, 6–2
See main article: 2012 ATP Vegeta Croatia Open Umag – Doubles. David Marrero / Fernando Verdasco defeated Marcel Granollers / Marc López 6–3, 7–6(7–4)
