Punishment is an important method for the ruling class to discipline criminals and alert people. According to historical records, a systematic punishment system was already existent during the Xia Dynasty. The “Ancient Five Punishments” recorded in Book of Documents occupies an important position in ancient Chinese punishments. Because they were all corporal punishment and the execution methods were extremely cruel so they were abolished in the Han Dynasty. The execution process of corporal punishment depends on the use of various knives. Therefore, punishment in ancient China is closely related to the “knife”. Shuo Wen Jie Zi contains a large number of Chinese characters related to punishment, and they are closely related to the “Ancient Five Punishments”. “刵（Er）”, as an ear-cutting penalty, can be traced back to the Zhou Dynasty or even earlier, and has similar meaning with the words “聝(Guo)” and “取（Q u）”. “㓷（Yi）” and “劓(Yi)” are variants of each other, and they were widely used as a penalty for cutting the nose only before the Han Dynasty. “刖(Yue)” means the punishment of cutting the legs, which has same meaning with the words “剕(Fei)” and “跀(Yue)”, but it was different from the word of “膑(Bin)” though they have similar meaning. The three characters “ (Xing)”, “刭(Jing)” and “刎(Wen)” can be explained by each other, and they all refer to the punishment of beheading. “罚(Fa)” means punishment for minor crimes. This word and the word of “刑(Xing)” meaning the punishment for serious crimes constitute the phrase of “刑罚(Xingfa)” in Chinese.