Trump, who was in Fort Wayne ahead of Tuesday's Indiana primaries, said, "We can't continue to allow China to rape our country."
He continued, "That's what they're doing. It's the greatest theft in the history of the world."
Ahead of the headline-making line, Trump said that America's "$500 billion trade deficit" with China can be turned around, telling the crowd "we have the cards."
"Don't forget, we're like the piggybank that's being robbed," Trump, 69, said. "We have the cards. We have a lot of power with China."
The phrase is one that Trump has used before, according to CNN. Back in 2011, he asserted that "China is raping this country" as he toured a defense manufacturer in New Hampshire.
Sally Field calls Donald Trump overrated
Trump hopes to clinch his spot as the Republican nominee on Tuesday, and eliminate any chance at a contested convention.
The crucial May primary comes just after the billionaire businessman was slammed by President Obama during his final White House Correspondents' Dinner speech.
"The Republican establishment is incredulous that he's their most likely nominee," Obama said to the dinner's audience, which included Trump's sons and their wives. "Shocking. They say Donald lacks the foreign policy experience to be president. But in fairness he has spent years meeting with leaders around the world. Miss Sweden, Miss Argentina …"