The two journalists were detained in July after they were captured in Ethiopia with rebels from the Ogaden National Liberation Front (ONLF).
The men were found guilty of the charges last week.
They say they were just doing their jobs as journalists.
Prosecutors had asked for longer sentences of up to 18 years, but Judge Shemsu Sirgaga, who presided in the case, said 11 years was appropriate.
"This sentence should satisfy the goal of peace and security," the AFP news agency quoted him as saying.
A lawyer for the journalists, Abebe Balcha, said they would decide later this week whether to appeal.
"I am not satisfied, as a lawyer for the defendants - I do not agree with the decision," he said.