Fast Track Court Judge Nazre Imam Ansari found the five guilty of kidnapping and murdering Amrit Raj Tomar of Harija Haata of Bihar's Bhojpur district in August 2010 and ordered their execution.
The five had thrown acid on the face of the victim after killing him to hide his identity.
The court also slapped a fine of Rs 35,000 on Arjun Chaurasia, who is one of the convicts and Rs 10,000 on the other four.
The other four are Binod Chaurasia (brother of Arjun Chaurasia), Nishu Kumar, Ashok Prasad and Tarkeshwar Prasad.