Chittagong Divisional Speedy Trial Tribunal Judge Md Mohitul Hoque Anam Chowdhury gave the verdict Tuesday morning.
The court also acquitted four others from the charge.
Tribunal's Public Prosecutor Aiyub Khan confirmed the matter to the Dhaka Tribune.
Oliullah was hacked to death on the night of Eid at Hongkorpur village under Kachua upazila in Chandpur on July 30, 2014.
Later, Oliullah's wife Joynob Begun filed a case with Kachua police station.