This paper describes how to derive audit criterion, audit domain, detail technology, and functional check items which are core of hospital information system, consisting of OCS, EMR, and PACS. Using the check items listed above, we investigated the objective validity for the construction audit of hospital information system. As a result, the derived audit criterion, audit domain, detail technology, and functional check items were verified as check items for audit. Since using the current audit check items of public area is insufficient to construct efficient, reliable, and stable hospital information system, we suggest adopting the hospital information system audit area, audit check items, and process that are presented in this paper.