A device for measuring displacement of a pantograph including image capturing means adapted to be placed on a roof of a car for capturing an image of a pantograph, and image processing means for acquiring displacement of the pantograph by performing image processing on an input image captured by the image capturing means, wherein the image processing means comprise: input image creating means for creating an input image by using an image signal inputted from the image capturing means; template setting means for acquiring, as a template, a marker pattern obtained by extracting a marker portion from an image acquired in advance; image-division processing means for dividing the input image into a predetermined number of sections on the basis of a resolution of each of pixels obtained by calibration means; template scaling processing means for scaling up or down the template for each of the sections of the input image on the basis of the resolution of the section; pattern-matching processing means for detecting a pixel position of a marker in the input image by using the template and the input image; and pantograph displacement calculating means for calculating actual displacement of the pantograph on the basis of the pixel position of the marker; characterized in that the image processing means further comprise: filtering processing means for performing smoothing processing on data on the displacement of the pantograph; and acceleration outputting means for outputting acceleration of the pantograph calculated on the basis of the data on the displacement of the pantograph smoothed by the smoothing processing means; wherein the pattern-matching processing means are adapted to set a pitch at which to shift the template, in accordance with a value representing correlation to the template and detected from the input image. input image creating means for creating an input image by using an image signal inputted from the image capturing means; template setting means for acquiring, as a template, a marker pattern obtained by extracting a marker portion from an image acquired in advance; image-division processing means for dividing the input image into a predetermined number of sections on the basis of a resolution of each of pixels obtained by calibration means; template scaling processing means for scaling up or down the template for each of the sections of the input image on the basis of the resolution of the section; pattern-matching processing means for detecting a pixel position of a marker in the input image by using the template and the input image; and pantograph displacement calculating means for calculating actual displacement of the pantograph on the basis of the pixel position of the marker; characterized in that the image processing means further comprise: filtering processing means for performing smoothing processing on data on the displacement of the pantograph; and acceleration outputting means for outputting acceleration of the pantograph calculated on the basis of the data on the displacement of the pantograph smoothed by the smoothing processing means; wherein the pattern-matching processing means are adapted to set a pitch at which to shift the template, in accordance with a value representing correlation to the template and detected from the input image. filtering processing means for performing smoothing processing on data on the displacement of the pantograph; and acceleration outputting means for outputting acceleration of the pantograph calculated on the basis of the data on the displacement of the pantograph smoothed by the smoothing processing means; wherein the pattern-matching processing means are adapted to set a pitch at which to shift the template, in accordance with a value representing correlation to the template and detected from the input image.