The paper proposes multiple sound sources localization method using directional pattern of a microphone array. Directional localization is achieved by using delay and sum beam forming (DSBF) and proposed main-lobe canceling method (MLC) using microphone directional pattern. The system subtracts higher intensity sound sources by using the directional pattern of a microphone array at each frequency, then it can localize multiple different pressure sound sources sequentially. We developed the 32ch microphone array to demonstrate the efficacy of proposed method. The design of the microphone array by beam forming simulation increases the resolution of the localization procedure and it's robustness to ambient noise. The octagonal array we developed achieved lower side-lobes during beam forming. We implement MLC on a mobile robot equipped with the octagonal microphone array. The experimental result shows that the system provides accurate and robust sound localization for multiple different sound sources during moving.