The present invention relates to a pose estimation method of an interventional medical device using a single-view X-ray image which is captured using a bendable interventional medical device equipped with a plurality of radiopaque markers and using an X-ray source. The pose estimation method includes an operation (a) of defining a circle assuming that the interventional medical device is bent at a constant curvature, an operation (b) of extracting a position value of the marker from an X-ray image obtained by the X-ray source projecting X-rays onto the markers, and an operation (c) of setting a projection plane and estimating a shape of the circle using a position value of the marker extracted from a projected image obtained by perspective-projecting the circle onto the projection plane and using the position value of the marker extracted from the X-ray image.