Four adults accused of abusing children at a circus training school west of Sydney deny the allegations against them, a court has heard.

Seven people linked to the business in the Blue Mountains were arrested on Monday and had 127 charges laid against them over allegations they physically and sexually abused three boys younger than eight between 2014 and 2016.

The boys, who were known to them, were allegedly forced to produce child exploitation material and reportedly had to take part in "rituals" where they had blood taken from them and were told to drink it.

The business caters to children with and without disabilities.

A man aged 18 and two women aged 17 and 20 appeared at a children's court on Tuesday where they did not apply for bail on charges including aggravated kidnapping, sexual intercourse with a child under 10, aggravated sexual assault, and producing child abuse material.

The 18-year-old man was charged with 42 of the 127 total offences.

The remaining four charged, who are part of the same extended family, faced Penrith Local Court on Tuesday afternoon.

Their lawyer Bryan Wrench said the adults - three women aged 26, 29 and 58 and a man aged 52 - had been aware of the allegations against them since September 2017.

He entered pleas of not guilty for all charges.

"They simply say 'we didn't do this and there is another side to this story'," Mr Wrench said.

He said the four, whose names cannot be published, had never been in custody before and intended to apply for bail on February 16.

Supporters of the 58-year-old woman were in court when the matter was mentioned. She is accused of 43 offences including having sexual intercourse with a child under 10.

The 26-year-old woman faces 13 charges, including aggravated sexual assault in company and detaining for advantage, while the 29-year-old woman has been charged with five counts of aggravated sexual assault in company depriving liberty and three counts of common assault.

The 52-year-old man faces three charges of aggravated sexual assault of a child under 10 in company, making child abuse material, and using a child under 14 to make child abuse material.

The group were arrested on Monday morning by detectives from the Child Abuse Squad's Strike Force Baillieu, which was formed in July 2017 and investigated the allegations for more than six months.

Police said investigations by the strike force are continuing.

"Anyone with concerns about suspected child abuse or exploitation should call Crime Stoppers on 1800 333 000," a police spokesperson said.

The matter will return to court later this month.