A police spokesman said seven guards were arrested in the illegal protest outside their employer's offices in Cape Town.
The dispute with local security firm Stallion comes after similar problems during last year's Confederations Cup, a dress rehearsal for this tournament.
Police said they had permanently taken over security at four venues; the showpiece Soccer City stadium and Ellis Park in Johannesburg, and the newly-built arenas in Cape Town and Durban. They were already guarding the coastal stadium in Port Elizabeth.
The move, which requires at least 4,000 police officers, follows a wage dispute between stewards, assigned to perform security inside the stadiums by the local organising committee, and Stallion Security.
