This study aims to describe one aspect in sociolinguistics which focused on the form of code switching and code mixing and the causal factors in the novel KukejarCintakeNegeri China by NinitYunita. This research used qualitative descriptive method with a sample of quotes from conversations between characters. The data collection technique used in this research is document analysis (content analysis). The theory used in this study is that code switching is a transition event from one code to another, while code mixing is the use of two or more languages by incorporating elements of one language into another language. The results of this study are, 1) there are two forms of code switching, namely internal code switching and external code switching. Symptoms of codemixing are interwoven in four forms, namely code-mixing the insertion of elements in the form of words, phrases, baster, and clauses. 2) the factors causing code switching are related to the speaker, the interlocutor, the presence of a third speaker, and simply being prestigious. Factors causing code-mixing include the attitude and language background of the speakers.

Keywords : Sociolinguistics, Code switching, Code mixing, Novel.