Through studying on the development of urban spatial morphology of Xi'an, Weihe River, which is one of the most important nature factors, has a important effect to the city form, the selection of the townsite, and the improvement of urban spatial morphology. 纵观西安城市空间形态演进历程,渭河水系作为一个重要的自然生态要素,具有多方面的功能,对城市形成与发展、城址变迁、形态演化等都产生了深刻影响。