The problem of distributive justice has been widely discussed by Western and Chinese students of Marxism. This interest results from the historical transformation of the Soviet Union and Eastern Europe at the end of the 1980s, and also from the crucial transition in China beginning in the late 1970s. Taking the basic principle of distributive justice as a reward according to the effort this paper discusses the differences between liberal thinkers (John Rawls and Robert Nozick) and Karl Marx. It deals with the concept of 'private property', or even 'private ownership'. Marx sees that the principle has been betrayed under the condition of private ownership: capitalist exploits workers and he hides this with the replacement of private ownership by public ownership; at last the principle of justice is replaced by the principle called beyond justice. Nozick sees the private ownership as the natural result of the principle (he regards it as self-ownership), Rawls shares the position with Nozick, but improve it with 'justice as fairness' which combines the principle of justice with the principle called beyond justice. Both Nozick and Rawls do not suspect that the principle itself would be betrayed under the condition of private ownership.