The invention easily provides blood glucose values and blood glucose value information within a period or range desired by a user without imposing cumbersome operation on the user. The invention easily provides blood glucose values and blood glucose value information within a period or range desired by a user without imposing cumbersome operation on the user by acquiring blood glucose levels measured by a blood glucose level measuring device (5) and date/time of measurement at which the blood glucose levels are measured, displaying a line graph (81) obtained by plotting the blood glucose values within a predetermined period and a slide bar (88), for example, on a graph display screen image (70), and plotting, if the slide bar (88) is moved in parallel, only the blood glucose values corresponding to a preceding period backdating in response to the amount of movement of the slide bar (88) on a line graph (81) along a time series.
