Steam injection has been applied successfully worldwide. The main objectives of this simulation study are to investigate the influences of steam quality, steam injection rates, well spacing, and well completion on the performance and oil recovery by cyclic and continuous steam injection modes into a Middle Eastern heavy oil reservoir. The ultimate goal of this study is to design a complete steam injection process capable to provide the highest cumulative oil recovery. Screening criteria has been applied for the reservoir to select the steam injection as the most appropriate enhanced oil recovery (EOR) method. The geological and fluid models were well-established and used with other reservoir rock, fluid, petrophysical data plus production history data to develop the best history matching for the reservoir under development. The effects of different injection injection rates, well completion and well spacing have been investigated. Heat distribution profile at different injection rates is developed plus water cut curves for different time intervals over 20 years. The influence of different types of well completion of open hole and selected perforated zones are also studied for different numbers of injectors and producers. The steam quality is optimized under different conditions for all proposed scenarios. The results indicated that the application of the open-hole well completion and the increase of steam injection rate increased the attained production rate for different steam quality and different well spacing. The optimum steam quality is determined and used for different proposed combinations of the abovelisted factors in this reservoir. The results also indicated that the application of selected perforation well completion is better than open hole completion because it is proven to provide better heat distribution throughout the pay zone. The results of this study develop a systematic approach for optimization the application of both cyclic and continuous steam processes considering heat distribution, well completion and variable parameters of the reservoir under development. Copyright © 2015 Society of Petroleum Engineers.