The background of this research is the massive promotion done by Go-Jek using advertisement media, especially commercial media on printed media or electronic media. Go-Jek advertisement concerned about local wisdom and implement high creativity. The advertising language used by Go-Jek advertisement is very interactive though it is short and simple hence it could attract the attention of the customer.

The objective of this research to find out the speech act. This research implements a descriptive qualitative method. Using this method, we will know the details of the structure of Go-Jek advertisement using the speech act theory. First, the researcher does the problem mapping. Then, continue by doing a research review to find the related source. Third, the researcher conducts observation and data taking to be analyzed. Lastly, the researcher concludes.

The results of this research are as follows; the speech act forms found in this research are the locution and illocution form. Kinds of speech act found are direct speech act and indirect speech act, the literal direct speech act, and non-literal indirect speech act. Meanwhile, the functions of the speech act found in the Go-Jek advertisement billboard are the declaration, representative, and commissive.

Keywords: Discourse Analysis, Speech Act, Go-Jek advertisement.