An internal report found 106 cases of underage labor, The Guardian newspaper of Britain reported Friday.
The report also uncovered a number of other offenses, including mandatory pregnancy tests and the use of bonded workers whose wages are confiscated to pay off debts imposed by recruitment agencies, among other things.
A Chinese supplier called Guangdong Real Faith Pingzhou Electronics, which made a circuit board component, has been dropped by Apple after 74 children under the age of 16 were recruited to work on the company's production lines.
Apple alleged that the children were knowingly recruited to work at the company by one of the region's largest labor agencies, Shenzhen Quanshun Human Resources.
"Underage labor is a subject no company wants to be associated with, so as a result I don't believe it gets the attention it deserves, and as a result it doesn't get fixed like it should," Jeff Williams, senior vice president of operations at Apple, has said.
Williams has vowed to eradicate the practice, but said it could take some time.