Suljović played in his third World Cup of Darts and second with Maik Langendorf in February 2013, but they finished bottom of Group A, losing to Japan 4–5 and England 2–5. He lost in the last 16 of the first European Tour event of 2013 to John Part 5–6. At the next event, the European Darts Trophy, Suljović had his best ever result on the PDC circuit by reaching the semi-finals. He saw off Scott Rand (6–5), Michael Smith (6–4), Andy Smith (6–0) and Kim Huybrechts (6–4), before losing to Wes Newton 6–4. Suljović was beaten 5–4 by Mark Lawrence in the first round of the UK Open, and 6–4 by Adrian Lewis in the first round of the European Championship. Suljović qualified for the World Matchplay for the first time in his career, but lost 10–4 to Raymond van Barneveld in the first round. In November, he won through to the semi-finals of the 13th Players Championship where he lost 6–1 against Brendan Dolan.