The characteristic and the formation process of moraine hill in the Dalian area along the coast are analyzed from the phenomenon of the Quaternary incompact layer covering the Dalian red clay. The aggregation deposition, the characteristic about the terrestrial and thalassic red clay in the Dalian is demonstrated, and the formation age of the Dalian red clay is determined before the Quaternary glacial age. Furthermore, it is demonstrated that the Dalian red clay is one of the key layers of ancient geographical and climate in the Dalian area.