The Oil and Gas industry is since decades aware that the time of “easy oil” is ending. Most of the world's largest producing fields are nearing depletion, and most of the remaining reserves are considered challenging to recover. This fact motivates the industry to develop and implement innovative EOR techniques to enhance the oil recovery. In fact, EOR techniques aim to modify reservoir parameters either by increasing the mobility ratio (Eq. 13) or by improving the capillary number (Eq. 5). The first goal of the thesis is to examine the effect of decreasing IFT and mobility ratio by flooding different solutions for oil displacement in glass microfluidic devices (micromodels) in order to investigate pore-level displacement mechanisms for EOR. The experiments have been performed using surfactant, polymer and surfactant-polymer flooding; aqueous solutions with different concentrations were injected into microchips saturated with oil from Matzen field (16TH reservoir). The injection experiments were performed in secondary and tertiary recovery modes. The results observed from the tests showed that both surfactant flooding and surfactant-polymer flooding yield to the highest recovery factor due to their ability to reduce IFT, the place by enhancing the mobility ratio, while the pure water flooding had the lowest recovery factor. Furthermore, the addition of surfactant to the injection water may lead to foam generation. Another focus of thesis was to study foam generation mechanisms and to analyse foam quality by investigating the bubble sizes and by the quantification of the characteristic times for the evolution of the foam. In addition, an investigation was carried out to examine the relationship between the bubble sizes and bubble mobility. The experiment result showed that the small bubbles have higher velocity compared to the larger ones,