Provided is a three-dimensional object emergence detecting device capable of detecting the emergence of a three-dimensional object rapidly and correctly at low costs.Based on a bird's-eye view image 30 taken by a camera 21 mounted in a vehicle 20, the three-dimensional object emergence detecting device detects the emergence of a three-dimensional object 22 in the vicinity of the vehicle. From the bird's-eye view image 30, the three-dimensional object emergence detecting device extracts orthogonal-direction characteristic components 46 and 47, which are on the bird's-eye view image 30 and has directions 36 and 37 orthogonal to a view direction 33 of the camera 21, and based on amounts of the extracted orthogonal-direction characteristic components 46 and 47, detects the emergence of the three-dimensional object 22. This prevents from erroneously detecting incidental changes in the image, such as sway of sunshine or movement of a shadow, as the emergence of the three-dimensional object.