Blake Lively doesn't want Justin Baldoni's lawyer to take her deposition, but she won't say why not ... so says the lawyer himself.

Bryan Freedman -- the attorney representing the actor in a series of different lawsuits -- and his law firm have submitted a letter to the judge ... claiming Lively and her legal team don't want Freedman to take her deposition in her lawsuit against Baldoni.

Freedman and his associates claim they object to him taking the deposition because of "unspecified statements" he's made about her in the past. Freedman's team then claims Lively's side didn't elaborate on their grounds for objection.

BF says he's not aware of a situation that would allow the person being deposed to dictate which lawyer can take the deposition ... claiming parties in lawsuits "simply do not have the right to dictate which of their opponents' attorneys may or may not take their deposition or perform any other aspect" of their client's case.

It's no secret Lively's not a fan of Baldoni's outspoken lawyer ... asking a court earlier this month to stop Freedman from making any more public statements about the case.

As you know ... last month, Blake filed a lawsuit alleging Justin sexually harassed her on the set of "It Ends With Us." Baldoni has fired black with a $400 million lawsuit against Blake and her husband, Ryan Reynolds.

We've spoken with Freedman about the case on "TMZ Live" ... discussing smear campaigns in Hollywood. Both Blake and Justin are accusing the other of embarking on a reputation-damaging smear campaign.

We've reached out to Freedman and Lively about this letter ... so far, no word back.