This paper attempts to find out the origin of the pronunciation of 車 che as 居 ju in modern Chinese dialects. First of all, although the explanation in (1) lacks crucial evidence, the fact 車 possessing the pronunciation of 居 ju does objectively exist. Then (2) the related documentations in history and all kinds of information on pronunciation comparisons, as well as the arguments by scholars of different dynasties, e.g. Wang Xianqian's ”Shi Ming Shu Zheng Bu”, are arranged. Additionally, contemporary scholars' knowledge on ”車 as 居” is examined in (3). Finally the paper concludes in (4) that 車 pronouncing as 居 ju after ”Guang Yun” is a result of civilization.