The charges against Tahmid Hasib Khan, one of the freed Gulshan cafe siege hostages, of not cooperating with police in the investigation have been dropped.
A Dhaka court on Sunday acquitted him in the non-prosecution case brought against him by police.
"The charges against him have not been proven. So the court acquitted him," defence counsel Matiur Rahman said, reports bdnews24.com.
Tahmid and former North South University teacher Hasanat Karim were among 13 hostages freed from the Holey Artisan Bakery and O' Kitchen at Dhaka's Gulshan early on July 2.
At least 20 diners, including 17 foreign nationals, and two policemen were killed before the rescue raid.
All the freed hostages were taken to the Detective Branch office and released after questioning, police said. But Tahmid and Hasanat did not return home. Their families alleged police were holding them in custody.
The duo were arrested from different places on Aug 3 as suspects under Section 54 of the Code Of Criminal Procedure.
The section allows police to arrest a person without a warrant if there is a reasonable suspicion that the person is involved in a crime.
After grilling Tahmid in custody for 14 days, police said they did not find his involvement in the July 1 attack on the upscale restaurant, which was reportedly claimed by the Islamic State.
Hasanat was shown arrested in the Gulshan attack case and is now being interrogated in police custody.
Tahmid, a businessman's son who has been studying in Canada, came to Bangladesh a day before the attack and went to the restaurant that day to meet friends, according to the family.
Police, however, pressed 'non-prosecution' charges against Tahmid over not cooperating with the investigators.
After being released on bail in October last year, Tahmid appeared before the court on Mar 14 this year and pleaded not guilty over the charges leveled by police.
The trial finished on Mar 21, when the court kept its verdict pending.