The attack, which took place late on Wednesday, occurred after the breaking of the fast during the Muslim holy month of Ramadan.
"After the prayer, the faithful gathered under a tent in Djakana," said a local official. "A suicide bomber exploded and killed 11 people. Four others were injured."
A Cameroonian army officer said the bomber was a young boy.
Since a regional offensive last year drove the insurgents from most of their strongholds, Boko Haram has been waging a guerrilla-style campaign targeting civilians. In Cameroon, teenage girls have killed dozens in suicide bombings.
More than 15,000 people have been killed and 2 million displaced in Nigeria and neighboring Chad, Niger and Cameroon during Boko Haram's seven-year campaign to create an Islamic caliphate in northeast Nigeria.
The group pledged its allegiance to Islamic State last year, although the practical extent of its links with the Syria- and Iraq-based group is not known.