Diddy says his legal archenemy, attorney Tony Buzbee, has no business filing lawsuits against him in at least one federal court … and he wants a judge to shut him down now.

Buzbee, of course, has filed dozens of lawsuits on behalf of clients accusing Diddy of sexual assaults and more — but, in particular, 22 of those cases were filed in federal court for the Southern District of New York … a district where Buzbee isn’t authorized to practice law.

Normally, this is not a big deal — it happens all the time — and attorneys, like Buzbee, would just file a pro hac vice, asking a judge for permission to practice in that jurisdiction. However, in new docs, Diddy’s team says Buzbee’s filed lawsuits before getting a judge to sign off on his pro hac vice … a major legal no-no.

Diddy says Jay-Z and his attorneys already pointed this out last fall when they filed a lawsuit against Buzbee, accusing him of extortion.

According to Diddy’s docs, Buzbee hasn’t even tried to get the judge’s approval in some cases, but still went ahead and filed lawsuits — and, on another occasion, he was actually denied admission to the Southern District of New York.

Diddy says the Chair of the Committee on Grievances issued an order on Feb. 13 denying Buzbee’s effort to gain admission to the SDNY … citing the fact Buzbee had been filing cases without first getting authorization.

Buzbee has now filed a proper pro hac vice, but Diddy is strongly opposing it, because Buzbee’s “egregious misconduct warrants denial of the privilege of appearing in this District.”

According to the docs, he’s also allegedly violated New York’s Rules of Professional Conduct for attorneys by repeatedly insisting Diddy is guilty of the criminal charges he’s facing … even though neither Buzbee or his clients are involved in that federal indictment.