In 1975, the same year when Brothers Union made their top-tier debut, Bablu got a national team call-up from Abdur Rahim who was the Bangladesh's coach at the time. Bablu travelled with the team to Malaysia where they took part in the Merdeka Cup. Bablu then played for the Bangladesh U19 team at the 1978 AFC Youth Championship in Dhaka. He also captained the U19 team during the 1980 AFC Youth Championship qualifiers, managed by his club coach Gafur Baloch. Bablu guided the youth national team to qualification as they finished group runners-up behind Qatar U19.
