In an interview with Corriere della Sera, Pope Francis said 'no-one has done more than the Church' in rooting out child abuse.
But the Survivors Network of those Abused by Priests (SNAP) said the pope's comments "reflect an archaic, defensive mindset that will not make kids safer".
"He's done nothing - literally nothing - that protects a single child, exposes a single predator or prevents a single cover up. He can claim his underlings are 'transparent', but history proves otherwise", the US-based victim support and campaign group said in a statement.
The comments were the pope's first response to a scathing UN report that denounced the Vatican for failing to stamp out child abuse and allowing systematic cover-ups.
"The Catholic Church is perhaps the only public institution to have acted with transparency and responsibility. No-one else has done more. Yet the Church is the only one to have been attacked," he said.
Last month's hard-hitting UN report called on the Church to remove clergy suspected of raping or molesting children.
It accused the Vatican of systematically placing the "preservation of the reputation of the Church and the alleged offender over the protection of child victims" - an accusation the Church heatedly rebuffed.
Barbara Blaine, the president of SNAP, later told The Local that the Vatican refuses to tackle abuse.