The earthquake started at 21:19:46 China Standard Time (CST, UTC+8) on 8 August 2017 in Zhangzha Town in Jiuzhaigou County (). It had magnitude 7.0. Cities as far away as Lanzhou, Chengdu and Xi'an felt the earthquake. The centre of the earthquake was 39 kilometres from the county seat of Jiuzhaigou County, 66 kilometres from Songpan County, 83 kilometres from Zhouqu County, 90 kilometres from Zoigê County, 105 kilometres from Longnan City, and 285 kilometres from Chengdu City.