City central business area stands as a city’s core of economic,social and cultural development,acts as a concentrated reflection of its comprehensive development,and plays a role of one of the most important public place. In order to equip the city central business area with better spatial quality of public service,this paper conducts a study on the evaluation system of its spatial quality. Firstly,it explicates the concept of “city central business area”, studies the development status of it,and defines the intendment of its spatial quality. Secondly, it elaborates the background and significance of spatial quality evaluation of city central business area,lists seven features of city central business area and nine characteristics of its space, and then summarizes its economic,social and cultural connotations,while concludes its evaluative targets and factors on that basis. Last,it employs the Analytic-hierarchy Process (AHP) to obtain an evaluation index system of spatial quality of city central business area, made of 3 layers,around 2 target layer index,12 elements combination layer index and 68 elements index layer index.This evaluation index system will provide scientific evaluation basis for better public service of city central business area. It’s expected that this index system will make scientific judgments and reviews on those elements which affect the quality of city central business area, and become the selection basics of continuously improving its spatial quality.