The 2004 Copa Petrobras Santiago was a professional tennis tournament played on outdoor red clay courts. It was part of the 2004 ATP Challenger Series. It took place in Santiago, Chile between 1 and 7 November 2004.
| Country | Player | Rank1 | Seed | |
|---|---|---|---|---|
 Spain | Óscar Hernández | 98 | 1 | |
 Brazil | Flávio Saretta | 111 | 2 | |
| Adrián García | 112 | 3 | ||
 Czech Republic | Jiří Vaněk | 132 | 4 | |
 Argentina | Edgardo Massa | 143 | 5 | |
| Argentina | Franco Squillari | 144 | 6 | |
| Brazil | André Sá | 159 | 7 | |
 Ecuador | Nicolás Lapentti | 169 | 8 |
The following players received wildcards into the singles main draw:
The following players received entry from the qualifying draw:
Francisco Cabello Diego Moyano
Marko Neunteibl Fernando VicenteSee main article: 2004 Copa Petrobras Santiago – Singles. Óscar Hernández def. Nicolás Lapentti, 7–6(7–4), 6–4
See main article: 2004 Copa Petrobras Santiago – Doubles. 
Enzo Artoni / Ignacio González King def. Brian Dabul / Damián Patriarca, 6–3, 6–0