The Second Stage of the 2011 Copa Santander Libertadores de América ran from February 9 to April 20, 2011 (match days: February 9, 15–17, 22–24, March 1–3, 8–10, 15–17, 22–24, 30–31, April 5–7, 12–14, 19–20).
[1] Twenty-six teams qualified directly into this round, to be joined by the six winners of the first stage.
The thirty-two teams were drawn into eight groups of four on November 25, 2010, in Asunción.
[2] The teams in each group played each other in a double round-robin format, playing the other teams in the group once at home and once away.
The following criteria were used for breaking ties on points:[3] The top two teams from each group advanced to the round of 16.