"It is a false allegation," North West police spokesperson Captain Adele Myburgh said, responding to an earlier report in the Saturday Star.
The newspaper reported that a used condom was allegedly found in the farmhouse bedroom where Terre'blanche was murdered.
"There was no condom found on the scene of the late Mr Eugene Terre'blanche".
Myburgh said police had no intention of "misleading" anyone about any facts in the case.
"I'm prepared to put my neck in a guillotine and you can have a go at it if I have been lying." She also said she had heard reports that the post mortem report had been leaked to the media.
"That is not true. It has not even left the site." Right wing leader Terre'Blanche was murdered at his farm outside Ventersdorp a week ago.
A man, aged 28, and a teenage boy, aged 15, have been charged with four crimes including the murder.
Terre'blanche's body was found by detectives with his pants pulled down and his genitals exposed.
The Saturday Star reported that a used condom had been found on the scene of the murder by investigators and sent for forensic testing.
One of the charges made against the alleged killers during court proceedings this week was of crimen injuria.
At the time prosecutor George Baloyi explained the charge of crimen injuria as: ".... they pulled down his [Terre'Blanche's] pants to his knees and exposed his private parts".
On Saturday, Mthunzi Mhaga, the spokesperson for the National Prosecuting Authority told the newspaper no further comment would be made on the charge.
"We've said enough. And that is that (the charge) is because Mr Terre'blanche's pants were pulled down to his knees and his private parts were showing. All other evidence will be presented at the trial."
Johannesburg lawyer Zola Majavu, who represents the minor, would neither confirm nor deny to the Saturday Star the discovery of the condom on the murder site.
AWB leader Steyn van Ronge at first told the newspaper that he "can't comment" on the alleged discovery of a used condom at the scene.
Later he told the newspaper that he was not aware of the discovery of any condom.
"If evidence is presented to support that, I will make a comment," he then said.
Along with the crimen injuria charge, farmworker Mahlangu, and the minor, have been charged with murder, house breaking and robbery with aggravating circumstances and attempted robbery with aggravating circumstances.
The case was postponed to April 14. The two had not yet pleaded to the charges.