A three-dimensional model generating device includes: a converted image generating unit that, for each of input images included in one or more items of video data and having mutually different viewpoints, generates a converted image from the input image that includes fewer pixels than the input image; a camera parameter estimating unit that detects features in the converted images and estimates, for each of the input images, a camera parameter at a capture time of the input image, based on a pair of similar features between two of the converted images; and a three-dimensional model generating unit that generates a three-dimensional model using the input images and the camera parameters.