Hydrocarbons in oil shale are significant for the output of fossil fuels and petrochemical materials; thus, the oil yield characterization is of great significance for efficient utilization and commercial exploitation of these resources. In this paper, we propose an evaluating means combined with electrical testing and terahertz (THz) measurements, named as resistivity-THz analysis (RTA), to characterize the oil shale from different places in China. Electrical and THz measurements were performed together to characterize the oil yield-dependent resistivity and THz absorption. Owing to the divergence in structures and compositions, both the electrical conductivity and THz parameters varied non-monotonic with the oil yield. However, electrically tunable THz wave absorption of oil shale can be realized by the linear correlation between the resistivity and THz attenuation coefficient, with the tunability varies monotonously with the oil yield. The results demonstrate that the carbon structures in kerogens are not only the conductive medium in oil shale but also the main source of THz absorption. As a non-contacting means for organic content characterization in oil shale, RTA is helpful to optimize the comprehensive utilization of this unconventional resource.