CAUPS(computer aided urban planning system) is an object and Agent based computer aided urban planning system.It changes the traditional urban planning pattern that needs multiple software to design cooperatively

and realizes a kind of novel urban planning pattern

i.e.

it firstly defines the urban objects that will be used by typical designers in planning

and then adds them to the evaluation sub-system

which will evaluate the design case automatically.One of the most important advantages is that it can increase the planning efficiency greatly.The method of design and implementation of CAUPS is presented in this paper.One of the main characters of CAUPS is that the relational data form in traditional GIS is transformed into the object-oriented form in CAUPS where object is regarded as the basic unit.Another main character of CAUPS is it uses the entity agents as its basic units during the process of urban planning.This system has been implemented successfully in the Planning Project of Hangzhou Westlake.