Inspectors have described relations between staff and prisoners at a South Yorkshire prison where riots took place in November 2010 as "very poor".
Inspectors also highlighted issues that affected HMP Moorland's ability to hold its prisoners safely.
Chief Inspector of Prisons Nick Hardwich said Moorland had "some solid strengths" but that "security intelligence" was not used effectively.
The riots in November caused thousands of pounds worth of damage.
Inspectors had talked to adults and young offenders at Moorland training prison shortly before and after the series of disturbances.
They were also concerned to find that a third of prisoners surveyed said they felt threatened and intimidated by staff.
And that "no attempt had been made to understand a 20% increase in security intelligence reports in the six months prior to the inspection."
Michael Spurr, Chief Executive of the National Offender Management Service (Noms) said: "Since the inspection, the Governor and staff have worked to improve staff-prisoner relations. Measures have also been put in place to improve the integration of adults and young offenders."