The idea of labor ethics is the important content of Marx's labor thought, and harmonious labor relations are the core propositions of Marx's work ethic. Marx thinks that the harmonious labor relations are the important foundation for the smooth development of labor, and the core of harmonious labor relations is the harmony of labor relations. Marx illustrates workers and its trade union, government, capital and its manager has different responsibility for the construction of harmonious labor relationship .Marx's idea of labor ethics is the important theoretical guidance of contemporary society, especially the construction of harmonious labor relations in contemporary socialist China.