An earthquake registering 6.4 Mw struck near the city of Yogyakarta on the southern side of the Indonesian island of Java, killing more than 5,700 people.

The 2006 Yogyakarta earthquake occurred at 05:53 local time on 27 May with a moment magnitude of 6.4 and a maximum MSK intensity of VIII (Damaging) in the Yogyakarta region of Java, Indonesia.

The moment magnitude scale is a measure of an earthquake's magnitude based on its seismic moment. M_w  was defined in a 1979 paper by Thomas C. Hanks and Hiroo Kanamori. Similar to the local magnitude/Richter scale (M_L ) defined by Charles Francis Richter in 1935, it uses a logarithmic scale; small earthquakes have approximately the same magnitudes on both scales. Despite the difference, news media often use the term "Richter scale" when referring to the moment magnitude scale.

Yogyakarta is the capital city of the Special Region of Yogyakarta in Indonesia, in the south-central part of the island of Java. As the only Indonesian royal city still ruled by a monarchy, Yogyakarta is regarded as an important centre for classical Javanese fine arts and culture such as ballet, batik textiles, drama, literature, music, poetry, silversmithing, visual arts, and wayang puppetry. Renowned as a centre of Indonesian education, Yogyakarta is home to a large student population and dozens of schools and universities, including Gadjah Mada University, the country's largest institute of higher education and one of its most prestigious.

Java is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 156.9 million people in mid 2024, projected to rise to 158 million at mid 2025, Java is the world's most populous island, home to approximately 56% of the Indonesian population while constituting only 7% of its land area. Indonesia's capital city, Jakarta, is on Java's northwestern coast.