The men, who are originally from China, have been convicted of murder and attempted murder for their role in the deadliest bombing in Thailand's history.
20 people died in the attack in August 2015, when a bomb exploded at a popular shrine in central Bangkok.
The defendants committed a single crime that violated several laws. The court has therefore sentenced them to the strictest punishment under the law, the death penalty, one of the judges said.
Both men have consistently denied the allegations.
