A procession of parents carried the boys, aged two to five and clad in white shirts and blue hats, through the mainly Muslim town of Kardjali on Saturday.
A team of doctors waited at the town’s main mosque to carry out the procedure.
Mass circumcision ceremonies are organised without charge for poor families.
Kardjali, in the southern Rhodope mountains, is the centre of Bulgaria's Turkish minority, which represents about 10% of the Balkan country's population of eight million.
The country’s Turkish Muslims previously suffered significant discrimination and mistreatment, notably in the mid-1980s, under a policy of Bulgarisation and cultural assimilation.
As a result, a large number of Bulgarian Turks fled to Turkey.
But most of them returned after the fall of communism, and in recent years they have enjoyed more legal protection of their cultural identity.