The medical institutes in Taiwan have committed to developing picture archiving communication systems (PACS) within years. Since, the investment is quite huge, it is important of setting up a model of evaluation to complement with the decision of constructing a successful PACS plan. According to this research, the factors of PACS construction are categorized into 8 major aspects and 28 items of criterion. Each factor is given different weighting based on the statistics of questionnaire investigation. This study applies grey relation analysis (GRA) to determine the priority of each manufacturer for constructing PACS. Finally, the evaluation of six PACS manufacturers is made by the PACS committee of the regional hospital.