The four women, two men and a 17-year-old girl face a total of 127 charges over the alleged abuse, which police say happened near Sydney between 2014 and 2016.
Local media reported that the suspects were involved in a circus school.
Police said the boys were all aged under eight, and knew their alleged attackers.
The allegations include kidnapping, sexual and physical assault, as well as the production of child abuse material.
According to Australian media, the circus school ran classes for children with and without disabilities.
The arrests followed "extensive investigations" that had begun with the establishing of a special police taskforce last July, authorities said.
The six adults facing charges are aged between 18 and 58.
All seven have been refused bail and will face a court in Sydney on Tuesday.