Effective and economic recovery of oil from fractured reservoirs by steamflooding rely on thorough understanding of the physical process mechanisms. The objective of this research is to study steamflooding mechanisms in fractured porous media using laboratory experiments and mathematical modeling. The experimental results have been published previously [1-3]. A mathematical model developed for simulating laboratory coreflood results is presented in this paper. The model is a two-dimensional, three phase, thermal simulator which includes the effects of gravity, capillarity and thermal swelling. Thermal effects on capillary pressure and relative permeabilities are included. Simulation and analysis of laboratory experiments are presented. Sensitivity studies demonstrate the effects of injection rate, pressure and temperature, fracture aperture, capillary pressure, and relative and absolute permeabilities on oil production.