There is a certain superstition about “delineating property rights perfectly and clearly”，and some people，not only in practice but also in theoretical field，believe that “the world can be efficient only when property rights are delineated clearly”. That idea has been thought as a symbol of economics of property rights with Ronald H. Coase as its founder. However，it is not Coase’s standpoint at all，and it is even，in some sense，clearly opposed to by Coase. Profound in thinking and prudent in wording，Coase would rather not use such terms as “property rights”，or “ownership”，not to mention the blurred concept of “delineating property rights perfectly and clearly”. For the purpose of understanding Coase，we must clarify different levels of key words Coase uses on rights，and the relationship of different parts of his important theses. With this article，the author hopes to bring back Coase’s opinions on rights as an analysis framework.