Abstract: The pre-evaluation of urban environment quality is to predict the changing tendency of the environment if the urban designing plan will be achieved.It is different from“the evaluation of the enyironmental effects”used now in a general sense.It can give a judge of a main city planning from a point view of the future environment change,which will help the authority to make a decision of which Plan would be better.

Key words: Shaanxi Province, spatiotemporal difference, ecosystem services