Extinction Rebellion staged a protest walk in 2019 to target Oxford University’s official Encaenia degree ceremony and highlight climate change.
The tradition did not go ahead in 2020 due to coronavirus.
In 2019 the environmental activists mocked the ancient ceremony with a parody event designed to raise awareness of climate change.
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Dozens of people took part in the 'Insania' walk from Radcliffe Square to Broad Street.
But it was a peaceful protest and did not disrupt the official ceremony.
The activists' own procession was designed to feature ‘awards’ for TV presenter David Attenborough and climate change activist Greta Thunberg.
Extinction Rebellion spokeswoman Hazel Dawe said at the time: “The Vice-Chancellor of the University of Oxford has told students that ‘Divestment will not have any tangible impact against climate change; it’s better to focus on research and green campus initiatives.
"This is muddled thinking and ignores the fact that the university’s international reputation requires it to show leadership and divest from fossil fuels.”
She added at the demonstration: "We need to act urgently - we need to act now - a major cause of the climate emergency is the burning of fossil fuels.
"We have lobbied the Vice-Chancellor to divest from fossil fuels - she has refused to do so, claiming the university investment is such a small proportion of the whole it will make little difference."
Ms Dawe said Wadham College had decided it would fully divest from fossil fuels and urged other colleges to commit to do the same.
At the university ceremony, honorary degrees were awarded to eight honorands including Professor Sir Simon Wessely, of The Royal Society of Medicine and movie director Martin Scorsese.
An Oxford University spokeswoman said before the demonstration: "We are aware of plans for the Extinction Rebellion event on the morning of June 26. "We are working with Thames Valley Police and the event’s organisers to ensure that the protest is peaceful, and does not disrupt the Encaenia ceremony."
Encaenia is the ceremony at which the university awards honorary degrees to distinguished men and women and commemorates its benefactors.
It is usually held on the Wednesday of ninth week during Trinity Term.
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