Playboy sent out an email to its subscribers Monday, after Mia expressed her pro-Hamas thoughts online -- the company said, "Mia has made disgusting and reprehensible comments celebrating Hamas’ attacks on Israel and the murder of innocent men, women and children."

It goes on to say the company encourages free speech and expression ... but adds, "We have a zero-tolerance policy for hate speech." Playboy says it's terminated its relationship with her, "including deleting Mia’s Playboy channel on our creator platform."

The former porn star-turned-influencer has been scrubbed from the company's Centerfold platform ... her page has been replaced with a simple "Not Found" graphic.

As we reported, Mia caught heat over the weekend, as Israel was being attacked by Hamas terrorists ... writing things like, "Tell the freedom fighters in Palestine to flip their phones and film horizontal."

Despite the hate she got, Mia doubled down -- writing, "I’d say supporting Palestine has lost me business opportunities, but I’m more angry at myself for not checking whether or not I was entering into business with Zionists."