Palacio played his first match with the Argentina national team on 8 March in a friendly match against Mexico which ended in a 1–1 draw at Los Angeles Memorial Coliseum.
Later that month, on 25 March, he played his first competitive match, a 2006 FIFA World Cup qualifier, against Bolivia, which ended with a 2–1 away victory, with Palacio playing the last eight minutes of the match.
He was selected by the coach José Pékerman for the following year's World Cup, and was given the shirt number 14.
He made his debut in the tournament, entering in the field in the 64th minute and helping the team to win the first match of Group C against the Ivory Coast in a 2–1 victory.
He did not play any more matches until the end of the tournament, with Argentina finishing the tournament in the quarter-finals after losing 4–2 on penalties against Germany.

Under new Argentina coach Alfio Basile, Palacio was selected for the 2007 Copa América and given the shirt number 7.
He played his first match in this tournament in the team's last match in Group C against Paraguay, starting and playing 90 minutes in a 1–0 victory at the Estadio Metropolitano de Fútbol de Lara.
Argentina finished as group winners, beating the United States, Colombia and Paraguay.
He made his second appearance after playing the last 12 minutes in a 3–0 win against Mexico, securing Argentina's place in the semi-finals of the tournament.
In the final, he was an unused substitute as Argentina lost 3–0 to rivals Brazil.

On 15 June 2008, more than three years after his debut with Argentina, Palacio scored his first goal for his country via equalizer in the 93rd minute in a 1–1 draw against Ecuador for the round 5 of 2010 World Cup qualification.
He played only two matches in 2008, and did not play any minute for the national team during 2009 and 2010, meaning that he was not included in the squad for the 2010 World Cup by coach Diego Maradona.

After his good form with Genoa during the second part of the 2010–11 season and first part of 2011–12, Palacio received his first call-up by new national team coach Alejandro Sabella for the 2014 World Cup qualifying match against Venezuela.
On 11 October 2011, he played his first match for the national team after a three-year absence, entering the field in the final 15 minutes of a 1–0 loss against Venezuela, with defender Fernando Amorebieta scoring the only goal of the match.

After an impressive 2012–13 season with Inter, Palacio became a regular member of the Argentina national team under Sabella.
During the qualifiers for the 2014 World Cup, he played eight matches and helped Argentina finish first place in its group with 32 points.
He scored his second goal for Argentina on 11 October 2013, scoring the third goal in the 3–1 victory against Peru in round 17 of the qualifiers.
During this year, he was an important player in Argentina's qualifiers, assisting several goals.

Palacio's good form continued even in 2014, scoring the third goal with the national team on 4 June 2014 in a 3–0 win against Trinidad and Tobago.
He scored after a corner kick taken by midfielder Ángel Di María.
Later in that match, he made a good run by dribbling the goalkeeper and assisted the third goal of the match scored by winger Ezequiel Lavezzi.
After playing another friendly match against Slovenia, the team traveled to Brazil to play in the 2014 World Cup; he was included on the list of 23 players selected by coach Alejandro Sabella to participate.
Notably he received a brilliant opportunity to score in the final against Germany during the 7th minute of extra time, when he received an exceptional pass from Marcos Rojo unmarked and alone on goal, but his attempt to lob the ball over Manuel Neuer missed the goal completely.

On 8 September 2014, at the age of 32, Palacio retired from international football, saying that there are better players to take his spot on the national team.
Palacio played his first match with the Argentina national team on 8 March in a friendly match against Mexico which ended in a 1–1 draw at Los Angeles Memorial Coliseum. Later that month, on 25 March, he played his first competitive match, a 2006 FIFA World Cup qualifier, against Bolivia, which ended with a 2–1 away victory, with Palacio playing the last eight minutes of the match. He was selected by the coach José Pékerman for the following year's World Cup, and was given the shirt number 14. He made his debut in the tournament, entering in the field in the 64th minute and helping the team to win the first match of Group C against the Ivory Coast in a 2–1 victory. He did not play any more matches until the end of the tournament, with Argentina finishing the tournament in the quarter-finals after losing 4–2 on penalties against Germany.
Under new Argentina coach Alfio Basile, Palacio was selected for the 2007 Copa América and given the shirt number 7. He played his first match in this tournament in the team's last match in Group C against Paraguay, starting and playing 90 minutes in a 1–0 victory at the Estadio Metropolitano de Fútbol de Lara. Argentina finished as group winners, beating the United States, Colombia and Paraguay. He made his second appearance after playing the last 12 minutes in a 3–0 win against Mexico, securing Argentina's place in the semi-finals of the tournament. In the final, he was an unused substitute as Argentina lost 3–0 to rivals Brazil.
On 15 June 2008, more than three years after his debut with Argentina, Palacio scored his first goal for his country via equalizer in the 93rd minute in a 1–1 draw against Ecuador for the round 5 of 2010 World Cup qualification. He played only two matches in 2008, and did not play any minute for the national team during 2009 and 2010, meaning that he was not included in the squad for the 2010 World Cup by coach Diego Maradona.
After his good form with Genoa during the second part of the 2010–11 season and first part of 2011–12, Palacio received his first call-up by new national team coach Alejandro Sabella for the 2014 World Cup qualifying match against Venezuela. On 11 October 2011, he played his first match for the national team after a three-year absence, entering the field in the final 15 minutes of a 1–0 loss against Venezuela, with defender Fernando Amorebieta scoring the only goal of the match.
After an impressive 2012–13 season with Inter, Palacio became a regular member of the Argentina national team under Sabella. During the qualifiers for the 2014 World Cup, he played eight matches and helped Argentina finish first place in its group with 32 points. He scored his second goal for Argentina on 11 October 2013, scoring the third goal in the 3–1 victory against Peru in round 17 of the qualifiers. During this year, he was an important player in Argentina's qualifiers, assisting several goals.
Palacio's good form continued even in 2014, scoring the third goal with the national team on 4 June 2014 in a 3–0 win against Trinidad and Tobago. He scored after a corner kick taken by midfielder Ángel Di María. Later in that match, he made a good run by dribbling the goalkeeper and assisted the third goal of the match scored by winger Ezequiel Lavezzi. After playing another friendly match against Slovenia, the team traveled to Brazil to play in the 2014 World Cup; he was included on the list of 23 players selected by coach Alejandro Sabella to participate. Notably he received a brilliant opportunity to score in the final against Germany during the 7th minute of extra time, when he received an exceptional pass from Marcos Rojo unmarked and alone on goal, but his attempt to lob the ball over Manuel Neuer missed the goal completely.
On 8 September 2014, at the age of 32, Palacio retired from international football, saying that there are better players to take his spot on the national team.
Rodrigo Palacio