Shimao is a Neolithic site in Shenmu County; Shaanxi; China. The site is located in the northern part of the Loess Plateau; on the southern edge of the Ordos Desert. It is dated to around 2000 BCE; near the end of the Longshan period; and is the largest known walled site of that period in China; at 400 hectares.

The city was surrounded by inner and outer stone walls; in contrast to the rammed earth walls typical of Longshan sites in the Central Plain and Shandong. The walls were 2.5 meters thick on average; with perimeters of approximately 4200 m and 5700 m respectively; and feature gates; turrets and watch towers.

The inner city contained a stone-walled platform; interpreted as a palatial complex; and densely packed residential zones; cemeteries and craft workshops. Unusual features include jade embedded in the city walls; possibly to provide spiritual protection; and paintings of geometrical patterns on the inner walls. Many human skulls were found under the city gate; suggesting ritual sacrifices during construction.