On 20 April 2013, a catastrophic earthquake of magnitude 7.0 struck the Lushan County, northwestern Sichuan Province, China. This earthquake named Lushan earthquake in China. The Lushan earthquake damaged many buildings. The situation of building loss is one basis for emergency relief and reconstruction. Thus, the building losses of the Lushan earthquake must be assessed. Remote sensing data and geographic information systems (GIS) can be employed to assess the building loss of the Lushan earthquake. The building losses assessment results for Lushan earthquake disaster utilization multisource remote sensing dada and GIS were reported in this paper. The assessment results indicated that 3.2% of buildings in the affected areas were complete collapsed. 12% and 12.5% of buildings were heavy damaged and slight damaged, respectively. The complete collapsed buildings, heavy damaged buildings, and slight damaged buildings mainly located at Danling County, Hongya County, Lushan County, Mingshan County, Qionglai County, Tianquan County, and Yingjing County.