For complex petroleum recovery processes, an experimental investigation is usually performed with a numerical simulation to study the recovery mechanism(s). In this paper, both physical and numerical simulations of the steam assisted gravity drainage (SAGD) process were performed. One of the objectives of the numerical investigation was to determine the match between numerical results with data generated from scaled model experiments. The Computer Modelling Group's (CMG) STARS(TM) thermal simulator was used. Results from the numerical simulation were found to be in reasonable agreement with those obtained from the experiments for oil production rates, and cumulative oil production. In addition, the steam chamber volume and temperature distribution were also examined. Effects of different parameters, such as steam injection pressure, vertical separation between injection and production wells, and reservoir thickness, on the performance of the SAGD process were investigated. They were observed to have the same effects on both experimental and numerical results. The numerical simulator was also used to study the influence of rock and fluid properties, such as oil viscosity, permeability, porosity, and the amount of heat loss from the reservoir to the surroundings.