The disclosure under freedom of information law showed at least 176 officers up to the rank of inspector were carrying out duties only for the Police Federation, costing the taxpayer an estimated £5.8 million a year, a newspaper reported.
It comes two days after Home Secretary Theresa May was barracked over budget cuts by delegates to the Federation's annual conference in Bournemouth.
The figures led one Tory MP to complain that public money was being "squandered" on the "histrionic" organisation.
Information was provided by 42 forces in England and Wales and showed wide differences between the number of federation representatives employed by each.
Derbyshire has six delegates while the Cheshire and Leicestershire forces have three and the Metropolitan has 19 full-time federation officers.
Manchester, Devon and Cornwall, and the West Midlands each had ten, the figures reported in the Daily Mail showed.
Tory MP Dominic Raab told the newspaper: "The hard-pressed taxpayer will be gob-smacked that millions of pounds of their money is being squandered subsidising the activities of the histrionic Police Federation, rather than mitigating pressure on local force budgets.
"When they see its chairman, Paul McKeever, stage-managing the ritual annual attempt to humiliate the Home Secretary for her common-sense proposals, many will feel that their money should have instead been spent on front-line policing."
Simon Reed, the Police Federation's vice chairman, said: "The Police Federation is a staff association for 134,000 police officers set up by Parliament. We represent police officers during grievances and welfare issues and, in the absence of industrial rights, act as the voice of officers.
"Federation representatives deal with all modern employment issues at a local level and are able to assist forces to deal with grievances and problems before they become legalistic and expensive."