As one of the most widespread linguistic phenomena, code-switching has attracted increasing attention nowadays. Inspired by previous studies in this field, this paper addresses code-switching under the guidance of Systemic Functional Linguistics (SFL), with the primary goal of analysing the interpersonal meanings of code-switching in three TV series. The research data were collected as follows: first, internet resources were examined to find three popular TV series with code-switching, namely "I Not Stupid," "Moonlight Resonance" and "Humble Abode;" second, the data were selected, classified and observed for analysis. As the focus of this paper is interpersonal meaning, functional theories were elaborated towards a single framework for interpersonal meanings of code-switching in two parts: appraisal theory and tenor in register. The first part aims to evaluate emotions which are embedded in code-switching. The second part deals with the roles and relationships between different participants. With these theories included in the research, qualitative analyses were conducted: first of all, sample data were categorised based on their grammatical structures; then interpersonal meanings of code-switching are discussed under the guidance of these functional theories to test the applicability of SFL in this field. It is concluded that code-switching in these TV series is a natural reflection of interpersonal meanings in daily life. People switch codes to express their emotions and negotiate the interpersonal relationships between different participants. It is hoped that the major findings of the present research will contribute to broadening the research scope of code-switching.