The 2003 Copa Nissan Sudamericana was the second edition of CONMEBOL's new international club tournament. It was won by Peruvian club Cienciano, who won the first international trophy for their club and the country. They also qualified to play in the 2004 Recopa Sudamericana.
First stage Argentina Preliminary
!colspan="5"|Argentina III Preliminary
!colspan="5"|Argentina IV Preliminary
Brazil Preliminary Qualifies to the Final Brazilian Preliminary
Brazil 1 Preliminary
Brazil 2 Preliminary
Brazil 3 Preliminary
Brazil 4 Preliminary
Venezuela/Bolivia/2002 Champion Preliminary First round
!colspan="5"|Venezuela Preliminary
Second round
!colspan="5"|Venezuela/San Lorenzo Preliminary
!colspan="5"|Bolivia Preliminary
Peru/Chile Preliminary
!colspan="5"|Chile Preliminary
!colspan="5"|Peru Preliminary
Colombia/Ecuador Preliminary
!colspan="5"|Colombia Preliminary
!colspan="5"|Ecuador Preliminary
Paraguay/Uruguay Preliminary
!colspan="5"|Paraguay Preliminary
!colspan="5"|Uruguay Preliminary
Second stage Argentina Zone
!colspan="5"|Quarterfinalist 4
!colspan="5"|Quarterfinalist 8
Brazil Zone
!colspan="5"|Quarterfinalist 2
!colspan="5"|Quarterfinalist 5
Venezuela/Bolivia/2002 Champion Zone
!colspan="5"|Quarterfinalist 6
Peru/Chile Zone
!colspan="5"|Quarterfinalist 1
Colombia/Ecuador Zone
!colspan="5"|Quarterfinalist 3
Paraguay/Uruguay Zone
!colspan="5"|Quarterfinalist 7
Bracket
Quarterfinals
Semifinals
Finals
External links CONMEBOL Sudamericana 2003