Northern Constabulary has said most of its officers and staff are opposed to the creation of a single Scottish police force.
The force which covers the Highlands and the Northern and Western isles held an internal staff survey on the plan.
Northern said 778 questionnaires were completed and 86.6% of the respondents voted against a single force.
The Scottish government has been a consulting on how to reform the police and fire service.
Earlier this month, Strathclye Police Chief Constable Stephen House said a national police force would be better equipped to deal with major incidents.
He said smaller individual forces could not respond alone to large-scale emergencies.
Northern Constabulary Chief Constable Ian Latimer has been opposed to any move towards a national force.
The force's internal survey showed 70% of its respondents favoured the retention of the constabulary.