When performing inspection of a tip of a suction nozzle, the tip of the suction nozzle is imaged, and an opening of the tip of the suction nozzle is identified based on the image data. With the image based on the image data, locations with less than a set brightness level inside a location with the set brightness level and greater is identified as the opening. The identified opening is divided into four regions by boundary lines, and the area of the opening is calculated for each of the regions. Based on the areas calculated for each region, it is determined whether the suction nozzle is good. By determining whether the suction nozzle is good based on the area of the opening for each region, it is possible to reliably determine whether the suction nozzle is good.