The Fengtu Charitable Granary in Qing dynasty is a warehouse building that local officials and gentlemen set up. It has an excellent site and a special building form. It reflects the majestic scene of the granary building in our modern architecture history. On the basis of natural geographical environment of the east of Guanzhong and the history of the ancient city of Chaoyi, the paper discusses how to validly integrate grain store against famine and military defense in the selection of the site, at the same time analyses the relation between the special building form and the grain store technology.