The full and rigorous self-discipline of the Party is the latest achievement of the exploration of the “Three Laws”by the Communist Party of China, and they are organically unified. To deeply understand and grasp the law of exercising full and rigorous self-discipline of the Party, we must put it in the background of “Three Laws”, which are the sources for theories, cognitive basis and guidance for practice in terms of the law of exercising full and rigorous self-discipline of the Party. It is necessary to follow the law of exercising full and rigorous self-discipline of the Party so as to meet the requirements of the“Three Laws”. As a product of the combination of the“Three Laws”with China’s realities in the new era, the law of exercising full and rigorous self-discipline of the Party is significant to improve both the theoretical and practical value of the“Three Laws” in Party building.