Ahead of the 2019–20 season, Haroun was linked a move away from the club, as Gent was interested in signing him. He ended the transfer speculation by signing a two–year contract, keeping him until 2021. At the start of the 2019–20 season, Haroun continued to establish himself in the starting eleven, playing in the midfield position, as well as, captain. He set up the club's first goal of the season, in a 4–1 win against Waasland-Beveren on 4 August 2019. Haroun started in every matches until he fractured his arm that kept him out for a month. It wasn't until on 19 January 2020 when Haroun returned to the starting line–up, in a 2–1 win against Cercle Brugge. However, his return was short–lived when he was suspended for one match. But Haroun made his return to the starting line–up, starting the whole game, in a 1–0 loss against Club Brugge on 2 February 2020. He then played in both legs of the Belgian Cup semi–finals against K.V. Kortrijk and beat them 2–1 on aggregate to reach the final. However, the season was cancelled because of the COVID-19 pandemic, resulting the club finished fourth place in the league. At the end of the 2019–20 season, Haroun made thirty–three appearances in all competitions.