Numerical spatial data builds the foundation of Geographic Information System (GIS) Data contains inherent errors and processed errors which provied information for manipulation, assessment and decision_making of geagraphic features. Digital image maps, digitized by scanners, provide the system presentation background in tour guiding system which combined with a Global Positional System (GPS). The aim of this exercise is to obtain the error distribution of whole maps, according to the measurement of difference between mesh data and geo-referenced images to assess the positional accuracy of digitized maps. People can legibly refer to the analysis reports and the corresponding error image, while considering the suitability of application of data rescource.