1. A measuring endoscope apparatus comprising: an endoscope that photoelectrically converts an image of an object to generate an imaging signal, a signal processing section that processes the imaging signal to generate image data, a distance-measuring section that calculates object distances for a plurality of points on the object using the image data, a display section that displays the image of the object based on the image data, and a measuring section that determines a display appearance of a first mark to indicate an inclination of the object in a depthwise direction of the image based on the object distances for the plurality of points on the object, wherein the measuring section determines the display appearance of the first mark such that one portion of the first mark that corresponds to part of the object that is closer is larger than another portion of the first mark that corresponds to part of the object that is farther away, wherein the display section displays the first mark.