More than 230 groups, advocating for the rights of Uyghurs, Tibetans, and South Mongolians, as well as Hong Kong, Chinese and international democracy advocates, signed a joint statement calling for "the immediate resignation of the United Nations High Commissioner for Human Rights".
They also urged UN Secretary-General Antonio Guterres to refrain from proposing a second term when her mandate expires at the end of August.
Bachelet has faced widespread criticism for not speaking out more forcefully against Chinese abuses during the long-planned trip, which took her to the far-western Xinjiang region, where China is alleged to have detained over a million Uyghurs and other Muslim minorities, as well as carried out forced sterilisation of women and coerced labour.
The United States has labelled China's actions in Xinjiang a "genocide" and "crimes against humanity", allegations vehemently denied by Beijing which says its security crackdown in the region was a necessary response to extremism.
The signatories of Wednesday's statement, which included a number of national and local chapters of the same groups, decried that Bachelet had "squandered a rare opportunity to promote accountability by failing to address the litany of systematic human rights violations committed by the Chinese authorities".
Instead, they said, "She whitewashed the Chinese government's human rights atrocities," and "legitimised Beijing's attempt to cover up its crimes by using the Chinese government's false 'counter-terrorism' framing".
They also decried that she had repeatedly referred to the detention camps in Xinjiang by the Chinese government's preferred term: "vocational education and training centres".
And they criticised the UN rights chief for failing to speak out about the leaked Xinjiang police files, which the media revealed as her trip began, showing top leaders in Beijing including President Xi Jinping calling for a forceful crackdown.
In particular, they lamented that she has so far failed to release a report on the rights situation in China, completed last year, despite mounting demands for it to be made public.
"The repeated, open-ended, and unexplained delays call into serious question the credibility of her office to fulfil its mandate," the statement said.
The signatories said Bachelet had been "entirely silent on the human rights crisis enveloping Tibet" during her four years in office, and had "grossly underplayed the crackdown" in Hong Kong.
"The failed visit by the high commissioner has not only worsened the human rights crisis of those living under the Chinese government's rule, but also severely compromised the integrity of the Office of the High Commissioner for Human Rights in promoting and protecting human rights globally," the statement said.
Bachelet is expected to face significant scrutiny from states over her China trip during the next week's session of the UN Human Rights Council in Geneva.