Kim Zolciak claims Kroy Biermann turned into the Grinch on Christmas ... because she told cops he stole her expensive prescription medication.

The reality TV star levies her latest accusation against Kroy in new police body cam footage obtained by TMZ ... telling cops in Georgia her estranged hubby broke into the place where she stores her meds.

Kim called cops to their home on Christmas and claimed Kroy stole a handful of medications that cost her over $1,500 at the pharmacy.

At the time, Kim and Kroy were living in the home despite going through a nasty divorce ... and were in the process of moving out.

Kim also accused Kroy of stealing her belongings a few weeks before Christmas in another police body cam interaction ... and the estranged couple's called cops to their home on a number of occasions as their divorce has dragged on.

It's funny, in the police report the responding officers notes ... "I was familiar with the residence as I had been there multiple times in the past for past incidents."

We reached out to Kroy ... so far, no word back.