Janko Tumbasević (Serbian Cyrillic: Јанко Тумбасевић; born 14 January 1985) is a Montenegrin professional footballer who plays as a defensive midfielder for Serbian club Mladost Lučani.

Tumbasević made his senior debut with Zeta under manager Nikola Rakojević in the second half of the 2001–02 First League of FR Yugoslavia.^[1] He made over 100 league appearances for the club and won the 2006–07 Montenegrin First League, while captaining the side.

In August 2007, Tumbasević was transferred to Vojvodina, alongside Žarko Korać. He spent the following four years at the club, before moving to Moldova and joining Dacia Chișinău. In the first half of the 2012–13 season, Tumbasević was on loan at Zimbru Chișinău, before returning to Dacia Chișinău in early 2013.

In June 2016, Tumbasević signed with Mladost Lučani.^[2] He spent three seasons with the club, making 102 appearances and scoring 14 goals across all competitions. After two years at TSC, Tumbasević returned to Mladost Lučani in June 2021.

Tumbasević represented FR Yugoslavia at the 2002 UEFA European Under-17 Championship, as the team were eliminated in the quarter-finals by England, thanks to Wayne Rooney's goal. He also made one appearance for Serbia and Montenegro at under-21 level.^[3]

At full international level, Tumbasević earned four caps for Montenegro, making his debut in the country's inaugural match, a 2–1 home friendly win over Hungary on 24 March 2007.^[4]

Zeta

• Montenegrin First League: 2006–07

Vojvodina

• Serbian Cup runner-up: 2009–10, 2010–11

Mladost Lučani

• Serbian Cup runner-up: 2017–18

Individual

• Serbian SuperLiga Player of the Week: 2021–22 (Round 22^[6])