A powerful earthquake and its aftershocks hit Niigata Prefecture in northern Japan, killing 35 people, injuring 2,200, and leaving 85,000 homeless or evacuated.

The Chūetsu earthquakes (中越地震, Chūetsu jishin) occurred in Niigata Prefecture, Japan, at 17:56 local time (08:56 UTC) on Saturday, October 23, 2004. The Japan Meteorological Agency (JMA) named it the "Heisei 16 Niigata Prefecture Chuetsu Earthquake" (平成16年新潟県中越地震, Heisei ju-roku-nen Niigata-ken Chuetsu Jishin). Niigata Prefecture is located in the Hokuriku region of Honshu, the largest island of Japan. The initial earthquake had a magnitude of 6.6 and caused noticeable shaking across almost half of Honshu, including parts of the Tōhoku, Hokuriku, Chūbu, and Kantō regions.