'The Real Housewives of Atlanta' alum filed a motion last Wednesday, October 9, making the allegation and also asking a judge to order Kroy to return her personal possessions ... according to online court records seen by TMZ.

The motions are sealed but sources familiar with the situation tell TMZ ... Kim's firing off about Kroy allegedly surveilling her within their home -- including one incident where we're told Kim says there's photos of Kroy passed out in her closet after spying on her.

As we've told you, a judge ordered that only Kim is allowed down in the basement, while Kroy gets the master bedroom ... but, our sources say Kim claims that hasn't stopped him -- with her alleging he went down into her private space while she was gone and took all the security cams she set up to stop him from intruding on her space.

Our sources say she's not trying to kick him out of their shared home ... instead, we're told Kim was expecting Kroy to eventually return her personal items, but he never did ... so now she's asking the court to get involved.

We're told the filing would also prevent Kroy from touching Kim's stuff going forward ... including personal notes Kim says he may have already gotten his hands on.

All in all, our sources say Kim's filing is similar to past claims she's made against Kroy in which she alleged he stole her phone and other personal belongings in January and May.

It sounds like this issue has been brewing for a while ... as we first reported, Kim called cops to their home back in May and claimed Kroy snatched her cell phone and locked himself in the master bedroom.

Kim and Kroy have a court order instructing them to stick to their halves of the house ... and Kim told cops she was unable to get the phone back from Kroy, and that he wouldn't give it back. For his part, police body cam footage showed Kroy denying having Kim's phone.

A similar incident unfolded in January, when Kim claimed Kroy took her personal belongings in an attempt to sell them ... an allegation Kroy also denied.