Shu Xin-yao & Lee Jeong-bok. 2015. “A comparative analysis of the internet nicknames used by Korean and Chinese netizen”. The Sociolinguistic Journal of Korea 23(3). 205~238. Internet nickname is a kind of temporary names that netizen want to use them to show the identity and differentiation from other netizen in the internet communication. The purpose of this paper is to compare and analyze the internet nicknames which are created and used distinctively in SNS of Korea and China. The main emphasis of this study is on the structures, the types of meanings, and making motivations of internet nicknames. The data are collected from the Twitter used by Korean netizen, and the Weibo used by Chinese netizen. The structural aspects of internet nicknames are divided into single structure and composite structure. The meaning types of internet nicknames are divided into ‘self-information’, ‘idol information’, ‘pursuit information’ and ‘the others’. The motivations of creating internet nicknames by netizen are divided into ‘linguistic efficiency motivation’, ‘creative expression motivation’, ‘play motivation’, ‘strengthen relation motivation’, and ‘psychological liberation motivation’. As a result of research, we could clarify the sameness and the difference of the linguistic culture on cyberspace between Korea and China by analyzing the internet nicknames.