SU(5) Grand Unified Model and Dark Matter

A dark matter model which is called w-matter or mirror dark matter is concretely constructed based on (f-SU(5))X(w-SU(5)) symmetry. There is no Higgs field and all masses originate from interactions in the present model. W-matter is dark matter relatively to f-matter and vice versa. In high-energy processes or when temperature is very high, visible matter and dark matter can transform from one into another. In such process energy seems to be non-conservational, because dark matter cannot be detected. In low-energy processes or when temperature is low, there is only gravitation interaction of dark matter for visible matter.