A three-dimensional object preview device includes a cross-sectional image data generation section configured to generate cross-sectional image data representing a cross-sectional shape of each layer of a three-dimensional object, a two-dimensional coordinate data acquisition section configured to acquire first two-dimensional coordinate data from the cross-sectional image data, a two-dimensional coordinate data conversion section configured to convert, using triangulation, the first two-dimensional coordinate data into second two-dimensional coordinate data, a three-dimensional coordinate data generation section configured to add Z-axis coordinate information to the second two-dimensional coordinate data to generate three-dimensional coordinate data, a layer image data generation section configured to add layer thickness information to the three-dimensional coordinate data, thus generating layer image data, a printing image data generation section configured to generate, using the layer image data, printing image data representing a three-dimensional model, and a display section configured to cause a display device to display the three-dimensional model.