Jeremy Meeks is absolutely certain he's done with his marriage ... he's filed to divorce his estranged wife ... TMZ has learned.

The so-called Hot Felon had filed separation docs back in July, breaking things off from Melissa Meeks ...who he'd been with for 8 years.

The separation came a few weeks after he was spotted making out with TopShop heir Chloe Green. He and Chloe have been inseparable ever since ... and clearly it's going well enough he's ready to pull the plug permanently.

He's requesting joint legal and physical custody of their 7-year-old son, Jeremy Jr.