Cardinal George Pell, Pope Francis's chief financial adviser said he would take a leave of absence as the Vatican's finance tsar and would return to Australia to fight the charges.
The Catholic Church said it would not pay the 76 year old's legal fees after Victoria Police charged him.
Institute of Public Affairs executive director John Roskam confirmed the fund's existence, according to the Sunday Herald Sun.
Roskam, a Catholic, said he had obtained an account number from "people assisting the cardinal".
He said he had passed those details on to Catholics who were keen to donate to Australia's most senior Catholic's legal defence.
He added: "I was asked by people how they could support the defence of Cardinal Pell.
"The point of this (fund) is that there are a lot of people who want to support the cardinal and want to give him the opportunity to clear his name."
The charges follow longstanding allegations that Cardinal Pell mishandled cases of clergy abuse while he was archbishop of Melbourne and later, Sydney.
Giving evidence the Australian Royal Commission into Institutional Responses to Child Sexual Abuse last year, Pell acknowledged "enormous mistakes" had been made by the church in allowing thousands of children to be abused by clergy.
Pell has been ordered to appear at Melbourne Magistrates' Court on 18th July.
