The history of the spread and development of Chinese characters in Korea is very long. Chinese characters were introduced into the Korean peninsula as early as in the period from the end of the Han Dynasty to the Three Kingdoms (A.D. 3C). Until the end of the 19th century, Chinese characters were the official writing system in Korea. The Korean peninsula has a history of using Chinese characters for over 1,500 years. It has an incomparably rich collection of ancient texts and documents written with Chinese characters. Of them are a considerable number of stone carvings that authentically recorded the profound literacy of the Korean people in the Middle Ages as far as the culture of Chinese characters is concerned. At the same time, these stone carvings are also of valuable reference for the developmental transformations and the configurational patterns since the formation of the clerical script, through the Wei-Jin period, the Sui and the Tan dynasties, and all the way through modern times. The present study takes as an example of the stone tablet of Master Chinkam Sŏnsa of the Silla era collected in Korean Grand Compendium of Ancient Inscriptions published by the Korean Studies Institute. I specifically summarized and analyzed the alternative script of ancient Chinese characters in the Korean stone carvings. I found out that there are characters written with different strokes or in a different internal structure, those which have been simplified, those which some parts have been added to or subtracted from, and those with a different position. Then I explored the formation and the developmental trajectory of individual variant forms of a Chinese character. Thus, I grasped the reasons for the formation of the variant Chinese characters in Korean ancient stone carvings as well as their writing characteristics.