This paper researches the spatial agglomeration status of the financial services with the GIS spatial analysis and the statistics of the SingTel Yellow Pages. The authors provide a case study of the central area of Kuiwen District in Weifang City. They analyze the characteristics of the spatial variation of the financial services from 2000 to 2008, and point out the evolution of trends in the financial services industry. As for the medium-sized cities, this paper concludes that the financial services industry is in a high degree of agglomeration in central area within CBD (the character of agglomeration performance is single core), and the agglomeration is mainly affected by the size of the cities and the policies. The level and size of a city restrict the level and scale of the financial institutions in medium-sized cities. Government policy makers encourage the financial services industry to develop within the districts. In specific aspects,the spatial and temporal evolution of the banking sectors in medium-sized cities shows the strong regular pattern, while the nonbank sectors evolution shows a relatively random pattern, but both of these phenomena present an "axial dispersion" trend and a "building-oriented" trend. The evolutionary process is consistent with urban development and the functions of cities' transformation. The spatial performances show the transition from an unbalanced pattern to a relatively balanced pattern. The evolution of the financial services of a medium-sized city can be roughly divided into the following four stages which are an initial formation period, the steady development period, the agglomeration and agglomeration period, and the diffusion period. During different periods, the features and characteristics of industrial development, spatial patterns, distribution and impact mechanism are different.