A sexing apparatus 100 includes irradiation means for irradiating each of hen eggs within a predetermined period of time from start of incubation with light having a predetermined wavelength, imaging means for imaging each of the irradiated hen eggs, means for generating a sexing model using, as training data, a result of separately sexing the hen eggs and image data obtained by the imaging of the hen eggs, and means for sexing a new target hen egg by inputting an image data obtained for the target hen egg by the irradiation means and the imaging means into the sexing model.