A method and an apparatus for detecting drowsiness using a reflected image on an eye iris are provided to accurately detect whether a driver is sleepy by using a visual ray blocking unit. An optical source(110) irradiates a predetermined near IR(InfraRed) ray on a user's face to obtain a face image. An image acquiring unit(130) acquires the near IR ray face image for a predetermined time interval after a vehicle is started and extracts the shape of the image of the optical source, which is focused on an eye iris. The acquired image is determined to be an arousal state. A visual ray is removed from the image of the user's face by using a visual ray blocking unit(120). The shape of the optical source image focused on the iris is extracted from the near IR ray face image. An image processor(140) compares the obtained image with the arousal state image to determine whether user's eyes are closed. The image processor detects drowsiness based on the duration of the closed eyes. An alarm generator(150) generates alarm sound to the user based on the detected result from the image processor.
drowsiness detection using reflected image on eye iris