Abstract: In light of the concept of modern stratigraphy,it is proposed that the Quaternary stratigraphic units may fall into two categories. The first category is characteristic stratigraphic units, including those related to petrology, biology, magnetism, soils,archeology and geomorphology jibe second category is attribute stratigraphic units,including climatic,chronologic and genetic stratigraphic units. It is considered that in the l: 50000 regional surveys one shouldchoose proper stratigraphic units according to the characteristics of Quaternary development inthe survey area for unit type classification and that generally one should give priority to characteristic stratigraphic units.