Paul addressed the allegations Monday on social media, saying ... "Let me be absolutely clear: I categorically deny any and all claims of improper conduct. Respect, integrity, and consent are values I hold dear, and I have always treated everyone with the utmost professionalism."

Oakenfold -- who many consider the godfather of electronic music -- adds ... "It is disheartening to see these baseless accusations, which appear to be nothing more than a calculated attempt to tarnish my reputation and extort money."

According to the lawsuit, obtained by TMZ, the woman claims Paul exposed himself and masturbated in front of her while she was on the job. She even claims he masturbated in her car and once pleasured himself in front of her 4 times in a single day.

The 24-year-old woman says she took a job at a management company and was assigned to be Paul's personal assistant in October, and she claims he pleasured himself in front of her on her first day ... and on 3 other occasions.

In the docs, the woman says she reported the alleged incidents to her bosses and was told she couldn't resume working if she didn't sign an NDA. She claims she eventually signed the NDA under duress and returned to work but says she was no longer assigned to Paul.

The woman claims she was given fewer hours and was ultimately laid off in March ... and now she's suing Paul and others for unspecified damages.

Paul's rep tells TMZ ... "Although she was not officially employed by him nor did she serve as his full-time assistant, it's important to note that Oakenfold had minimal contact with her, and they barely had any face-to-face interactions. He doesn’t even recall her name."

The rep also tells us Paul hasn't been served the court document.