Based on the function orientation of the new towns in General Planning for Beijing Municipality(2004-2020) and the condition of future economic growth and labor force demand,this paper makes a population prediction of Changping using edge-glide algorithm.It is pointed out that the population amount will decline under natural population growth,from 515 thousand in 2000 to 489 thousand in 2020.Along with the population and industry transfer from center of the municipality to outer district,the new town will have strong impact on function remission of the central city area and the population will increase rapidly in Changping.It is predicted that there will be increase of 520-630 thousand in Changping from 2000 to 2020.So it's important to take measures to meet the requirement of population growth and alleviate the function of city zone.