[2] Mamun was also a member of the Bangladesh national team that won its first international trophy, the Burma Cup in 1995, under coach Otto Pfister.

[3] Mamun Joarder started his youth career in Chuadanga, after passing various stages of selection of U-16 footballers he came to Dhaka to take part in the divisional league final match for Khulna Division.

In 1985, Azad Sporting Club coach Anjam gave Mamun the opportunity to play the last two matches of the Dhaka First Division League season.

[2] Abdus Salam Murshedy, who was the director of Mohammedan at the time, signed Mamun, after being impressed with his performance with Victoria SC during his second season at the club.

Mamun was heavily criticized by both the media and Mohammedan fans due to his sudden transfer to fellow title contenders.

However, Mohammedan took the lead early on the game, Abahani manager Salahuddin had named Mamun on the bench due to allegations of match fixing.

Mamun scored again after 5 minutes, this time he dribbled past 2 Mohammedan defenders to slot the ball into the net by beating goalkeeper Sayeed Hassan Kanan.

However, at the end of 1994 all four of them (except Monem Munna) including Mamun left Abahani to join Muktijoddha Sangsad KC, after the country's top three clubs Mohammedan, Abahani and Brothers Union made a gentleman's agreement to lower the salaries of lower the salaries of their star players.

Mamun's only trophy for the "freedom fighters" during his first stint at the club was the 1994 Federation Cup, which he won by defeating Abahani 3–2 in the final.

The injury Mamun sustained along with a knee meniscus surgery turned out to be detrimental to his career and lead to him soon losing his place in the Bangladesh national team.

On 23 August 2000, he played his final match against his former club Mohammedan in the Federation Cup at the Bangabandhu National Stadium.

[8] Mamun made his senior national team debut for Bangladesh during the 1990 Asian Games against Saudi Arabia, on 24 September 1990.

On 28 December 1991, Mamun scored his first senior goal for his country as Bangladesh secured bronze in the South Asian Games, defeating Nepal 2–0.

[4] In 1994, Mamun participated in the Qatar Independence Cup with Muktijoddha Sangsad KC, representing the national team.