Data security and informationization reliability systems are the primary problems in the construction of hospital informationization. The article analyzes three cluster technical principles of Windows operating system in details. Combined with the status and needs of Center Hospital's informationization in Yongzhou city, it proposes a program suitable for informationization in medium and large hospitals. Through simulation experiments and actual use testification in Central Hospital, this program can be a good solution to solve data security andapplication reliability, with promotion prospects.