The number of social media users in Indonesia is relatively high compared to other countries. In 2012, 19.5 million Indonesian are on Twitter. In contrast, most museums in Indonesia (both public and private museums) do not have marketing officer nor social media officer! Indonesian museums rarely use social media for promoting their programs or events. Within this paper I discuss the effectiveness of Twitter as social media marketing for museum events. As a case study I conduct research on Museum Ceria’s events. Museum Ceria is an independent museum educator in Jakarta which specialized in designing public programs within museums. The result of this research could be used as recommendation for museums in Indonesia to start using social media as their marketing strategies.