A method for detecting a position of mobile robot. The method includes receiving at a mobile robot an infrared signal generated from an infrared generator according to a rotation angle of the rotated infrared generator, determining an angle between the mobile robot and the infrared generator based on a specific frequency value of the received infrared signal and previously stored frequency values, receiving an ultrasonic signal oscillated from a ultrasonic signal oscillator when the infrared generator reaches a predetermined angle, calculating a distance between the mobile robot and the ultrasonic wave oscillator by multiplying a sound velocity to a time taken for receiving the ultrasonic signal by the mobile robot after being oscillated, and detecting a position of the mobile robot based on the determined angle and the calculated distance.