Three 17-year-old boys have been charged over the alleged group sexual assault of a 17-year-old girl in Sydney's south-west at the weekend.

Police said the girl was allegedly attacked at a home in the Macarthur region on Saturday.

On Wednesday about 7am, detectives carried out search warrants at a number of homes in the area.

Officers seized electronic devices and items for examination, police said.

Three boys were arrested and taken to Camden Police Station, where they were charged.

One of the boys was charged with 11 offences, including aggravated sexual assault in company, three counts of sexual intercourse without consent, sexual touching without consent and carry out sexual assault with another without consent.

Another boy was charged with eight offences, including six counts of aggravated sexual assault in company with others, common assault and sexual intercourse without consent.

The third boy has been charged with two counts of aggravated sexual assault in company with others.

All three have been refused bail and are due to appear in the children's court on Thursday.