Abstract: The classification of current soil parent material types has not yet formed a unified standard. Diverse classification methods were adopted by various industries based on their own needs. To meet the needs of agricultural geological surveys in Guangdong-Hong Kong-Macao region, the authors in this paper took the perspective of rock-soil system as a whole and analyzed the soil characteristics developed from different rocks. A classification scheme for the soil parent materials was proposed based on geological conditions. The study shows that there is a close genetic relationship between soil genesis, development, properties and the physical and chemical properties of the parent rock. The differences in geological conditions are the main factors leading to soil differentiation, significantly affecting the development of ecosystems and the quality of ecological environment. Through the analysis of the rock weathering and soil formation process, 4 primary level classifications were established in Guangdong-Hong Kong-Macao region, including Quaternary loose accumulation parent materials, sedimentary rock parent materials, igneous rock parent materials, and metamorphic rock parent materials, and 26 secondary classifications were also identified. The classification scheme could more accurately and objectively reflect the material transfer process from parent rock to parent material, to soil and the differences in energy distribution on the earth's surface. And it has important practical significance for evaluating soil resource levels, developing and utilizing land resources according to local conditions, and scientifically and rationally managing the ecological environment.