Kim Zolciak's Boyfriend Claims Estranged Wife Lied About Kroy Biermann Romance

Kim Zolciak's boyfriend, Kyle Mowitz, claims his estranged wife wasn't telling the truth about her relationship with Kim's estranged husband, Kroy Biermann ... and now he's asking a judge to keep the former NFL star away from his kids.

According to court docs, obtained by TMZ, Kyle says Jillian Green testified during a deposition in their divorce that she and Kroy were "just friends" and had only met once and weren't continuing to talk.

Kyle says Jillian also testified she didn't expect to have an ongoing relationship with Kroy and had no plans of having him around her children.

But months later, Kyle claims he found Kroy's vehicle parked outside the family's home while their kids were there. He also says text messages produced during the divorce show Jillian communicated with Kroy far more than she admitted under oath.

Kyle further claims neighbors have told him Kroy is frequently at the house.

In the filing, Kyle says he's concerned because of what he describes as Kroy's "unpredictable behavior" and his alleged history of mental and physical abuse involving both adults and children. He wants the court to bar Kroy from the home and from being around his kids.

Kyle also points out TMZ published photos earlier this year showing Jillian and Kroy getting cozy.

Under a temporary court order, Jillian has exclusive use of the former marital home. Kyle says he still keeps valuable wine and a collection of weapons inside the residence ... and he's asking the court for permission to enter the home, get the weapons, perform an inventory of the wine, and install a lock on the wine cellar.