The ship carrying the Bangladeshis will bring back Myanmar security personnel who crossed the border recently amid fighting with rebels
Judge Farhana Ferdous handed down the verdict on Sunday.
The recipients of the death penalty are Lukimuddin, 40, Mannan, 40, Asaduzzaman Mia, 42 and Jahirul Islam.
The court has also imposed a fine of Tk 20,000 on each of the four suspects.
The murder took place on Jun 6, 2013, said court police Inspector Md Tanvir. A case was started on Aug 13 of that year, he said.