Nine schools have complained about Geoffrey Owen during the last three years but this is the first complaint to be upheld by the Office for Standards in Education (Ofsted).
An Ofsted spokesman said last night that Mr Owen's position as a registered inspector was under review.
Christchurch infant school in Down End, Bristol said that Mr Owen was intimidating and negative when he took part in an inspection in July. Janita Hills, the headteacher, also complained that the report was "full of inaccuracies".
The school did not fail the inspection but was found to have a comparatively high percentage of unsatisfactory teaching.
The Ofsted spokesman said: "Most of the complaints about the conduct of this inspection have been upheld. These were complaints about the conduct of the registered inspector, the way he set the inspection up and his attitude to staff.
"We have never hitherto upheld any complaint about Mr Owen though some elements of previous complaints about his conduct have been upheld. His position is under review."
Mr Owen could be deregistered as an inspector.
Under the rules governing inspections, the school's report cannot be withdrawn. However, it has been offered a reinspection. A spokesman for South Gloucestershire council said that some staff at the school had asked for counselling because they were so distressed by the inspection.
"The school is very pleased with the response from Ofsted but they would rather they had not been put in this position."
Fourteen registered inspectors have been deregistered during the past 12 months and Ofsted has stopped dealing with 40 inspection contractors because of the quality of their work
Nigel de Gruchy, general secretary of the National Association of Schoolmasters Union of Women Teachers, which represents staff at the school, said: "There have been a number of complaints logged by our members in the past against this particular inspector. It was stretching credibility that so many teachers have all been wrong."