Polymer flooding is a proven enhanced oil recovery (EOR) technique that uses polymers to maintain a favorable mobility ratio between the displacing fluid (i.e., polymer solution) and the displaced fluid (i.e., oil) for the volumetric sweep efficiency to be improved and thus, oil recovery to be enhanced. Conversely, its applications were mainly geared towards sandstones, where the environmental conditions encountered by the polymers are insufficient to affect their initial properties severely. The decline in oil production besides the complexity of discovering new reservoirs diverted the attention towards extracting oil from more challenging reservoirs like carbonates. Carbonate reservoirs hold the largest portion of the world's oil reserves but they are known for their harsh conditions, including but not limited to high salinity, hardness, temperature and low permeability, which hamper the successful application of polymer flooding. This study aimed at evaluating eight different polymers for application in carbonate reservoirs subjected to different shear rates with the objective of identifying feasible and mechanically stable polymers under harsh conditions of salinity (196,000 ppm) and temperature (75℃). The evaluation procedure included bulk rheology, shear stability, filterability, oscillatory and injectivity tests. The bulk rheological tests proved the robustness of sulfonated polymers in resisting the harsh conditions of this study but suggested that under such conditions, there existed a maximum allowable ATBs content beyond which the ATBs based polymers might lose their high viscosifying power. Furthermore, the oscillatory tests revealed the side effect of incorporating the resistant monomer, ATBs, into polymer's formulation on the viscoelastic properties. Based on the performed oscillatory tests, ATBs seems to weaken the elastic properties of the polymers. The shear stability tests showed that the ATBs based polymers are more shear resistant than the zero ATBs polymers with the MW being the most dominant factor affecting the shear stability of the ATBs based polymers. As a result, the highly sulfonated polymer (SAV10) and the moderately sulfonated polymer (AN125), which have the lowest MW(s) among all the tested polymers, were the most shear resistant polymers. Furthermore, the filtration tests showed that these two polymers exhibited the best filterability. Consequently, these two polymers were selected for the subsequent injectivity tests. Six injectivity tests were carried out, using SAV10 and AN125 in their sheared and un-sheared states and SAV10MPM in its un-sheared state, in order to assess the potentiality of polymer flooding in very tight carbonates. Successful polymer propagation was observed for the highly sulfonated polymer, SAV10, in both its sheared and un-sheared states. Besides, its results showed that pre-shearing the polymer results in a significant improvement in its injectivity. Moreover, the highly sulfonated polymer SAV10MPM, which has a lower MW compared with SAV10 and AN125, showed successful accessibility. In spite of that, the injectivity performance of the sheared solution of SAV10 remained much better than SAV10MPM. Furthermore, the moderately sulfonated polymer, AN125, exhibited unsatisfactory injectivity performance characterized by higher resistance factors than the sheared solution of SAV10, regardless of its lower MW compared with SAV10, even at its sheared state. This signals the importance of the high sulfonation under such harsh conditions. All in all, the results of this study suggest that the best option for a successful polymer flooding project in tight carbonates under harsh conditions is to go for a highly sulfonated polymer with a moderate MW, after which the polymer has to be pretreated through shearing and filtering to ensure successful polymer propagation and better sweep efficiency. This is because a lower dosage would be required, besides the significant improvements in the polymer's injectivity.