In this study, a dynamic model of oil sludge pyrolysis in a rotary kiln with a solid heat carrier was developed. In the proposed model, both the particle motion in the rolling mode and oil sludge pyrolysis were taken into consideration. Saeman's model and a multiple-reaction model were involved to simulate the bed depth profile inside the rotary kiln based on the solid motion and the volatile evolution, respectively. Furthermore, the temperature profiles of three phases (solid carrier, oil sludge, and gaseous phase) in diverse conditions were predicated by combining pyrolysis kinetics, heat transfer, and motion equations. In the proposed model, the yields of CxHy, H-2, CO, and CO2 were successfully stimulated and predicted. The validity of the model was verified from both aspects of solid axial velocity and gas yields by comparing numerical values to literature reports and experimental data, respectively. This simulation practice was expected to provide an alternative approach to obtain helpful parameters for the designing of an industry-scale rotary kiln pyrolyzer.