Abstract: A face image generating method for recognizing face performed by a face image generating device to extract a face image from image frames collected from an image acquiring device and generate a face image for face recognition, includes: a first step of converting an RGB-based image frame received from the image acquiring device into a YCbCr image; a second step of setting a region satisfying a skin color condition in the YCbCr image as a face candidate region; a third step of determining a face region; a fifth step of calculating a degree of inclination of a side face; and a sixth step of generating a face image for recognition by converting the front face image and the side face image into different sizes according to a distance to the image acquiring device.