Yee said he received a fax that called him a Marxist and "Fish Head Leeland Lee." The letter continued by saying Limbaugh would kick Yee's "chink ass." It closed with the phrase "Death to all Marxists."
The letter also came with an illustration of a pick up truck with an American flag dragging the head of President Barack Obama in a noose.
It comes a week after Yee asked the conservative radio talk show host for an apology after Limbaugh made fun of the Chinese language.
Limbaugh was describing a Fox News broadcast that had faulty translation of a speech given by Chinese President Hu Jintao when for almost 20 seconds he spoke gibberish Chinese. "Normally they translate every couple of words, but Hu Jintao was just going chin chong, chin chong cha..." Limbaugh said before continuing to mimic the language.
Yee said of the threat, "To see, and to hear, and to receive these kinds of horrible statements and racist threats is truly angering."
"I thought we could end this by just having someone apologize."
Yee said the fax was turned over to the Senate sergeant-at-arms to investigate.