Object It is to provide a measured vital data preserving and providing system for healthcare, making it unnecessary to have an independent data base which requires a lot of time and a lot of cost for its preparation, and on the other hand, enabling to construct a unique website for healthcare in a short time and at a low cost. Means for Achieving the Object A data providing side server 30 comprises a measured vital data DB50 composed of measured vital data records including user's IDs and user's measured vital data, and an API library 60 for processing the measured vital data DB50. In response to responding to a request which is sent from a data utilizing side server 20 to utilize a selected function of the API library 60 by specifying the user's ID, a responding section 32 of the data providing side server 30 can process measured vital data records recorded in the measured vital data DB50 by means of the selected function of the API library 60 so as to a predetermined response to the data utilizing side server 20. Selected Figure FIG. 1