Thumbnail images indicating images of a display layouts prepared in advance or created by the user are stored together with display layout data, and the thumbnail images are displayed as a list on a layout thumbnail bar in an analysis result display window on the display screen. The analyzer looks at the images so as to grasp the content of each display layout and then selects an appropriate thumbnail image. As a result, a screen in which chromatograms, mass spectrums, or the like are assigned to each of the regions in the graph display region is created in accordance with the selected display layout and displayed on a monitor screen.