The purpose of this study is to analyse code-mixing used by social media influencers in Instagram. The method of this research is qualitative method and observation is uded to find the posts of influencers where they use code-mixing. Questioning to the influencers about the reasons they often use code-mixing through Instagram direct message or email are also done. The writer decided that the two familiar influencers from public figures are the main samples of this research. The result from this research is that the influencers use code mixing because they want Indonesian people to develop themselves by mastering English language and they want to give example to people, especially their followers that English can be fun and everyone can practice English. Being habit is also one of the reasons that they like to use code mixing. The Influencers use code-mixing in instagram in certain time, such as lunch time and after office hours, because those are the active time for them and their followers online in Instagram. It is evident that the use of code-mixing by the influencers arouse the followers interested and motivated to sharpen their English language and it could be as one of the parts in practicing the followers’ English through social media. It then becomes one of the way to learn more a foreign language through social media.