Abstract: Marx's theoretical conception of the social security system in the future society holds significant guiding value for the construction of the social security system of socialism with Chinese characteristics in the new era. On the basis of exposing the exploitative nature and functional limitations of the capitalist social security system, Marx proposed a theoretical conception of the social security system in the future society with national responsibility as the cornerstone and fairness and justice as the value orientation. Under the guidance of this thought, China's social security practice has gone through four historical stages: wartime security during the New Democratic Revolution period, comprehensive state-provided security during the socialist construction period, the multi-tiered system during the new era of reform and opening-up and socialist modernization, and high-quality development in the new era of socialism with Chinese characteristics. In the context of the new era, the construction of a modern social security system with Chinese characteristics should continue to be guided by Marxism, adhere to the leading responsibility of the state in the social security system, continuously enrich the fair connotation and practice of the social security system, and continue to expound the contemporary value of Marx's social security thought, thereby providing theoretical support and practical path guidance for system improvement.