Defending champion Novak Djokovic defeated Rafael Nadal in the final, 6–3, 6–4 to win the singles tennis title at the 2013 ATP World Tour Finals.

Nadal was attempting to complete the career Super Slam.

Stanislas Wawrinka made his debut at the event.

Standings are determined by: 1. number of wins; 2. number of matches; 3. in two-players-ties, head-to-head records; 4. in three-players-ties, percentage of sets won, or of games won initially to sort out a superior/inferior player, then head-to-head records; 5.

ATP rankings Standings are determined by: 1. number of wins; 2. number of matches; 3. in two-players-ties, head-to-head records; 4. in three-players-ties, percentage of sets won, or of games won initially to sort out a superior/inferior player, then head-to-head records; 5.