"Chinese, Japanese, dirty knees" is a racist playground chant that has been used to mock children of Asian origin.
[1] Other renderings give the chant as "Chinese, Japanese, dirty knees, look at these," with a breast-related gesture accompanying the "look at these" phrase (such as pinching the front of one's shirt into mock breasts).
[6] Gregory B. Lee, writing that "many a Chinese immigrant child over the past 100 years has had to endure" the chant, notes that "[t]he allusion to dirt in this ditty is not aleatory", linking it to the stereotype of unclean "Orientals".
[7] In 2020, the film Monster Hunter caused controversy on Chinese social media because of a pun that some critics said was a reference to the chant: In a scene, MC Jin's character jokingly says: "Look at my knees!
Although the filmmakers and actors denied that the line had anything to do with the chant, the film was removed from circulation, and Chinese authorities censored references to it online.