Reformasi is both a Malay and Indonesian word for reform or reformation. It may refer to the:
- Reformasi (Indonesia), a movement to dethrone Suharto as President in May 1998 and the post-Suharto era in Indonesia that began immediately after
- Reformasi (Malaysia), which was initiated in September 1998 by former Malaysian Deputy Prime Minister Anwar Ibrahim, immediately after he was sacked by former Prime Minister Mahathir Mohamad