"What he is saying now is not only shameful and wrong, it is dangerous," she added.
On Sunday, Trump, the front-runner Republican candidate, called for a "total and complete shutdown" of Muslims coming into the United States.
Throughout the week, Clinton, who once attended Trump's wedding because she said she thought it would be "entertaining," has assailed Trump for his proposal.
“You know he does traffic in prejudice and paranoia. It’s not only shameful, it’s dangerous," she said during a campaign event on Wednesday. "We have to enlist help from American Muslims, Muslims around the world, in defeating the radical Jihadist and the hateful ideology they have. Instead, Donald Trump is supplying them with new propaganda. He is playing right into their hands."