Serving and former police officers, teachers and soldiers are listed as members of the British National Party in a leaked document published online, BBC reported.
The list, which dates from 2007, has the names, addresses, jobs and phone numbers of more than 10,000 people.
Since 2004, police officers have been banned from being members of the BNP.
The party's leader, Nick Griffin, said the leak was "a disgraceful act of treachery" by former members and called for a police investigation.
In a statement on the BNP website, Mr Griffin said he had lodged a complaint with Dyfed-Powys Police on the grounds that the publication breached human rights and data protection laws.
Occupations ascribed to the listed names include teachers, a doctor, nurse, vicar and members of the armed forces.
While there is no ban on many of those professions joining the BNP, its right-wing political stance and whites-only membership policy are seen by many as incompatible with frontline public service.
Police officers, on the other hand, are formally banned from joining, a policy which is recognised in the list.
Alongside the name of a serving officer, the document states that there is "Discretion required re. employment concerns".
Peter Fahy, chief constable of Greater Manchester Police and spokesman for the Association of Chief Police Officers, said: "Membership or promotion of the BNP by any member of the police service, whether police officer or police staff, is prohibited.
"This is because such membership would be incompatible with our duty to promote equality under the Race Relations Amendment Act and would damage the confidence of minority communities."
The BNP said the publication could lead to identity theft and endanger children named in the list.
Some as young as 14 are included where their families have party memberships.
The publication prompted fear among BNP members using internet chatrooms.
One person wrote: "I'm also on the list, what is going on? I could lose my job."
Another said: "God help anyone who is in the Army, the prison service, healthcare, a police officer or a teacher."
Earlier this year, the BNP obtained an injunction at the High Court in Manchester banning any publication of the list.
Mr Griffin said the list was "essentially genuine", but a number of names of people who were not or are not party members had been added.
He claimed the leak was linked to next year's elections to the European Parliament and that those responsible were former members who had subsequently been sacked.
"Just six months before the proportional representation European Parliamentary elections give us the chance for a gigantic leap into the mainstream big-time, we get another leak intended to frighten the faint-hearted," he said.
The anti-immigration party has won council seats in recent years, and took a London Assembly seat in May.
Labour MPs are pushing for trade unions to be given the right to expel members who belong to the BNP without penalty.