According to the complexity and heterogeneity characteristics of the shale oil reservoir, a multi-scale digital core scanning experiment are conducted on the shale oil reservoir rocks in the Chang 73 submember in Jiyuan area. The digital rock models of different scales and types are established for numerical simulation of rock minerals, reservoir space, seepage and other characteristic parameters. The application of multi-scale digital rock technology in shale oil reservoir evaluation is then thoroughly analyzed. Results show that the reservoir texture of Chang 73 shale oil in Jiyuan area is developed, and the lithofacies types are siliceous shale, mixed shale, siliceous clay shale and clay-rich siliceous shale. The reservoir space mainly consists of sub-micron matrix pores and millimeter-level bedding fractures, and matrix pores mainly include organic pores, clay pores and micro-fractures. The permeability of reservoir rock matrix is poor, and the existence of bedding fractures can greatly improve the permeability of the reservoir. This study forms a relatively complete multi-scale digital core evaluation experimental technology and method of shale oil reservoir, which helps and optimizes the elaborated evaluation and effective development strategy of shale oil reservoir.