Abstract: BIM technology has the characteristics of visualization and simulation. Its application in engineering detailed design and construction management on the site is more and more extensive. Based on BIM technology, The application value of geological simulation and construction organization simulation in the construction of deep foundation pit engineering is also gradually prominent. In order to solve the problems of complex engineering geological conditions, narrow construction site, various support forms and tight construction period, BIM technology is applied in the construction of underground works of the project. Firstly, the original data such as geological survey report and borehole are imported into Bentley codes. The geological body model is created by the combination of Bentley platform and the Empirical Bayesian Kriging method (EBK). Secondly, based on coupling geological model and pile foundation model, the theoretical length of cast-in-place pile can be checked and derived by interpolation method. The reasonable control of the pile length in site pile construction can be guided according to the above method. Combined with the application and verification of practical engineering, the research results show that the application of geological simulation and site layout simulation based on BIM can effectively solve the problems such as pile length control and construction organization in the construction process of complex geological and underground engineering. The quality of the engineering can be improved, and the construction period can also be shorted.