Medical record should enable doctors to comprehend the patient's history and select suitable medical treatment. In paper based medical records, medical events (examination, treatment etc.) are recorded successively, and problem oriented recording is difficult to be applied to patients with much information and a long history. Consequently it is not easy to understand the patient's history from paper based medical records. In order to solve this problem, we developed the flow sheet system in our electronic medical record (EMR). To make a flow sheet, we analyzed the structure of the medical event data. In this paper we introduced the medical event information model for our EMR. Furthermore, we clarified the specification of the data presentation on the flow sheet. We developed the flow sheet on the basis of these analyses. Because there are 3 layers in the vertical axis of the flow sheet, many items of the medical event can be displayed on the screen. When user clicks the cell, the corresponding detail data including images are shown. This system functions to link medical event items with a problem, and shows the bundled items on the flow sheet when the user selects the problem. We implemented this system in Osaka University Hospital. The number of the types of medical events and those of detail events in inpatients are 5.0±1.7 (mean±SD) and 60±47, respectively. The medical doctors in Osaka University Hospital evaluated this system, and concludes that the flow sheet data presentation makes comprehension of the patient's history easier than paper based records. As to the function of bundling the items relevant to the problem, they feel it is especially useful for patients with chronic disease. Thus the flow sheet data presentation in EMR is useful for medical practice.