in july 2017, jung joined danish superliga club brøndby if on a one-year loan deal reuniting with former rb leipzig coach alexander zorniger. on 23 july 2017, made his superliga-debut in 3–2 away loss to fc nordsjælland. during the 2017–18 season, jung made 29 league appearances in which he scored one goal. on 10 may 2018, he played as brøndby beat silkeborg if 3–1 in the 2017–18 danish cup final.