Asrul Alias, a technician, was held under the Internal Security Act (ISA) in August, the Ministry of Home Affairs (MHA) said.
He has been placed under a two-year Restriction Order, which curtails his movements and activities, after investigations, it said, adding that Asrul will undergo religious counselling during this period.
Meanwhile, two Bangladeshi nationals, who were detained in April this year for being supporters of ISIS, were repatriated last month after investigations were completed.
The MHA had earlier said that all eight Bangladeshis, who were migrant workers in Singapore, were detained under the ISA and were members of a secret group called Islamic State in Bangladesh (ISB) that was set up in March this year.
Six of the eight Bangladeshis had contributed funds towards the purchase of firearms for the group's plans in Bangladesh, and were convicted of terror financing. They have been sentenced to between two and five years' jail, the ministry said today.