A graph display method for a graph display apparatus including a display device, the graph display method characterized by the steps of: setting (S1 to S3) an XY coordinate system, to which a display range in an X-direction and a Y-direction is set, to a display area of the display device and displaying a graph of a function in the coordinate system; setting a scroll direction and a scroll speed according to an operation performed by a user; determining (U2, U3) whether, among characteristic parts of the coordinate system and the graph, any characteristic part cuts across a center of the display area in the X-direction or in the Y-direction when the displayed graph is moved in the scroll direction; (i) in case that it is determined that any characteristic part cuts across the center of the display area in the X-direction or in the Y-direction when the displayed graph is moved in the scroll direction; specifying, from among characteristic parts of the coordinate system and the graph, a characteristic part which cuts first across a center of the display area in the X-direction or in the Y-direction, when the displayed graph is moved in the scroll direction; calculating a movement amount for the specified characteristic part to reach the center of the display area; calculating a change amount of the display range of the coordinate system on the basis of the calculated movement amount and the set scroll speed repeatedly changing (U7 to U9) the display range, which is set to the coordinate system, on the basis of the calculated change amount until the calculated movement amount is reached and displaying (U7 to U9) the graph of the function within the display range each time changing the display range; and (ii) in case that it is determined that any characteristic part does not cut across the center of the display area in the X-direction or in the Y-direction when the displayed graph is moved in the scroll direction: not scrolling the displayed graph. setting (S1 to S3) an XY coordinate system, to which a display range in an X-direction and a Y-direction is set, to a display area of the display device and displaying a graph of a function in the coordinate system; setting a scroll direction and a scroll speed according to an operation performed by a user; determining (U2, U3) whether, among characteristic parts of the coordinate system and the graph, any characteristic part cuts across a center of the display area in the X-direction or in the Y-direction when the displayed graph is moved in the scroll direction; (i) in case that it is determined that any characteristic part cuts across the center of the display area in the X-direction or in the Y-direction when the displayed graph is moved in the scroll direction; specifying, from among characteristic parts of the coordinate system and the graph, a characteristic part which cuts first across a center of the display area in the X-direction or in the Y-direction, when the displayed graph is moved in the scroll direction; calculating a movement amount for the specified characteristic part to reach the center of the display area; calculating a change amount of the display range of the coordinate system on the basis of the calculated movement amount and the set scroll speed repeatedly changing (U7 to U9) the display range, which is set to the coordinate system, on the basis of the calculated change amount until the calculated movement amount is reached and displaying (U7 to U9) the graph of the function within the display range each time changing the display range; and (ii) in case that it is determined that any characteristic part does not cut across the center of the display area in the X-direction or in the Y-direction when the displayed graph is moved in the scroll direction: not scrolling the displayed graph. (i) in case that it is determined that any characteristic part cuts across the center of the display area in the X-direction or in the Y-direction when the displayed graph is moved in the scroll direction; specifying, from among characteristic parts of the coordinate system and the graph, a characteristic part which cuts first across a center of the display area in the X-direction or in the Y-direction, when the displayed graph is moved in the scroll direction; calculating a movement amount for the specified characteristic part to reach the center of the display area; calculating a change amount of the display range of the coordinate system on the basis of the calculated movement amount and the set scroll speed repeatedly changing (U7 to U9) the display range, which is set to the coordinate system, on the basis of the calculated change amount until the calculated movement amount is reached and displaying (U7 to U9) the graph of the function within the display range each time changing the display range; and (ii) in case that it is determined that any characteristic part does not cut across the center of the display area in the X-direction or in the Y-direction when the displayed graph is moved in the scroll direction: not scrolling the displayed graph.