The league’s statement has come in response to a story in The Times newspaper on Friday, which alleged that an employee of the charity had asked an IT expert whether he would be able to hack into the email of Tim Bonner, chief executive of the pro-hunting organisation the Countryside Alliance.
But in a statement, the League Against Cruel Sports said the allegation was "nonsense", and was "motivated purely by ex-trustees with a grudge".
The statement said: "These allegations are completely false. It is nonsense to say the league sought to hack the computer of the leader of the Countryside Alliance.
"It is also completely false to claim that the Charity Commission is investigating the league over this. We have had no such notification from them about this and expect none.
"This story is motivated purely by ex-trustees with a grudge against the league and who clearly felt it in the best interests of the anti-hunt movement to take their story to a pro-hunting newspaper."
The Times story claims that Chris Williamson, the Labour MP for Derby North and a former board member for the League Against Cruel Sports, had made a complaint to the Charity Commission about the allegations.
In a statement, Williamson said he had been suspended and then expelled from the charity’s board after raising concerns about the actions of people in the senior management team and other trustees.
Williamson’s statement said he had serious questions to ask about the charity’s finances and had heard allegations of harassment and bullying at the charity.
He said that nine trustees had left since July and called for an emergency general meeting to discuss the future of the charity.
"These are critical days for the League Against Cruel Sports," Williamson said. "Hunters are continuing to pursue and illegally kill wild mammals for sport with apparent impunity.
"Yet the remaining trustees are failing in their duty to provide effective governance to the charity. They are potentially putting the very existence of the league at risk by ineffectual oversight of the organisation.
"This could not just cause untold damage to the league, but also fatally undermine the animal welfare and rights movement, and all that we hold dear and stand for."
In its statement, the charity said Williamson had been expelled "after he supported someone who was abusing members of staff" at the league and had rarely attended board meetings for several years.
The statement said that he was offered the opportunity to make his case to the board 12 times, but did not accept those offers.
Speaking to Third Sector, Williamson – who has been a member of the board since 1979 – said the league’s claims about him were "absolutely absurd and offensive". He said he was in Europe at the time the board had made the offer and was at the Labour Party conference for other dates put forward.
He said he had requested a face-to-face meeting, rather than the phone conference that was offered to him, in which to make his case.
Williamson said that the claims he was supporting someone accused of abusing the charity’s staff were a "misrepresentation" of his support for a long-standing member of the charity and prominent anti-blood sports campaigner.
The Charity Commission was unable to supply a comment before publication of this story on Monday morning.