The Hollywood star said he "felt the need to get ahead" of the situation and to share his "concerns" before a story was published.
He said a former employee was accusing him of performing a sex act in front of her more than 30 years ago.
Douglas told Deadline: "This is a complete lie, fabrication, no truth to it whatsoever."
He said his lawyer contacted him in December, telling him a media outlet was planning to run a story about the woman's claims.