In Western-made works, Asian characters, especially those who are otherwise unassuming Funny Foreigners, are likely to know some kind of martial arts and demonstrate it proficiently, if not superlatively. For instance, the stereotypical Japanese character in many Western works written in the first half of the 20th century will probably demonstrate his jujitsu skills on some other character at some point.
See also Everybody Was Kung-Fu Fighting. All Chinese People Know Kung-Fu is a similar trope, but is about how Japanese (one Asian group) view Chinese (another Asian group). Anthropomorphic animal artists, often Chinese, will usually be Fighting Pandas. All Monks Know Kung-Fu is this trope applied to all kinds of monks. Can lead to a Chop Sockey.
All Asians Know Martial Arts has been suggested to play 1 roles. Click below to see other actors suggested for each role, and vote for who you think would play the role best.