On basis of the special and complex geological conditions in Chengdu area and the features of Metro works, the author analyzes the important and difficult aspects in the geotechnical investigations of Metro works by means of analyzing the major engineering geological issues in the construction of Metro works. The author states that comprehensive investigation and prospecting technologies, such as geological investigation, borehole prospecting, shaft prospecting, geophysical prospecting, insitu test and laboratory test, should be properly selected. Furthermore, the author recommends some rational and practical engineering countermeasures for the design, construction and monitoring of Metro works.