Tristan Thompson is trying to keep a tightly-sealed lid on info from his latest paternity case -- asking a judge to silence the woman who claims she's carrying his child from leaking info about the case ... while he continues to blast her as being out for fortune and fame.
The NBA star filed an emergency petition Tuesday in Harris County, TX -- asking the judge to issue a gag order in the case ... barring the parties (himself and Maralee Nichols) from speaking out about the case as it plays out in court.
Tristan points to multiple instances in which he believes Maralee has violated what he claims is a confidentiality order the judge orally granted earlier in the case after she sued him over paternity.
In the docs, obtained by TMZ, Tristan claims Maralee has been doing interviews with the media, leaking personal info and even taking to IG and other social media to spread what he says are blatant lies about himself and his family. Specifically, he claims certain Snapchat messages -- which Maralee has claimed were sent to her by Tristan -- were fabricated.
The reason Tristan thinks she's doing all this is "to achieve some sort of notoriety and gain for herself in this lawsuit."
Bottom line ... Tristan wants to keep this entire proceeding under wraps, including any discovery or evidence submitted by either side. He also wants the court to sanction Maralee for the alleged leaks.
To hit that point home, he wants a judge to force her to fork over a $30k bond to ensure she has some money on the line if she breaks the confidentiality order.
As we reported ... Maralee says Tristan is the father of a baby that's due any day now, something he's denied. She also claims he tried to pay her to keep quiet about the whole thing, in the amount of $75k.