“I shudder to imagine the amount of damage that could have been seen,” judge Kiarie Waweru Kiarie told the court in the capital Nairobi.
Ahmed Mohammed and Sayed Mansour, who were arrested last June, were found guilty of possessing 15 kilos (33 pounds) of the powerful explosive RDX.
The court said they had suspected links to a terror network planning bombings in Mombasa and Nairobi.
“I have considered their individual pleas,” Kiarie said, but then added that the “cry of victims of previous terrorist attacks is louder.”
The men, who denied the charges, are said to have hidden the explosives in the port city of Mombasa.