Sonar (Sound Navigation and Ranging) was covertly created by few countries during the reign of World War II. SONAR can be used to detect some moving object. It helps in the measurement of distance and angle from the observer. It works on the principle of Doppler shift. The designing of cheaper SONAR system for security purpose is the requirement of an industry. In this research Paper, the designing and implementation of Arduino based SONAR system using ultrasonic sensor are presented. The device is able to detect the object, calculate its distance (up to 30cm) and can determine the elevation angle. It provides a cheaper solution for security purposes.