Abstarct: Corrosion of steel reinforcement is one of the most significant factors reducing the durability and service life of reinforced concrete structures in aggressive environments, particularly under marine conditions. Ordinary concrete, due to its weakness in crack control and high permeability to aggressive ions, does not perform effectively in such environments, which has led researchers to focus on the use of fiber reinforced concrete. Although steel fibers considerably enhance the mechanical properties of concrete, challenges such as the corrosion of these fibers and the occurrence of pitting corrosion restrict their application in corrosive environments. Therefore, the use of non-mextallic fibers, which not only address the shortcomings of steel fibers but also exhibit high resistance to corrosion and harsh environmental conditions, is an undeniable necessity. Among these, twisted basalt fibers, as a new generation of non-mextallic reinforcements with characteristics such as high tensile strength, appropriate modulus of elasticity, environmental stability, and desirable resistance to corrosive agents, represent an efficient option for improving corrosion protection of steel reinforcement and enhancing the durability and service life of concrete structures in aggressive environments. The primary objective of this research is to investigate the effect of incorporating twisted basalt fibers on mitigating the corrosion of steel reinforcement in aggressive and corrosive environments, particularly in regions with high humidity and the presence of chloride and sulfate ions, such as marine areas in the north and south of the Iran. Accordingly, a comprehensive experimental program was designed and conducted, including pull-out tests of twisted basalt fibers embedded in the concrete matrix at various inclination angles (0°, 30°, 45°, and 60°) and embedment lengths (8, 15, and 22 mm) to evaluate their bond behavior and mechanical interlock with the concrete matrix. In addition, a series of mechanical tests (compressive strength, tensile strength, and flexural strength) and durability tests (water penetration, electrical resistivity, water absorption, and accelerated corrosion of reinforcement) were carried out using different fiber volume fractions (0, 0.5, 1.0, and 1.8%). The results indicate that increasing the embedment length enhances the fiber–matrix bond strength, frictional resistance, and adhesion behavior. Furthermore, increasing the fiber content significantly improves tensile strength and flexural performance, while the improvement in compressive strength is relatively limited, demonstrating that the main role of twisted basalt fibers lies in crack control and the enhancement of tensile performance. From a durability perspective, the inclusion of twisted basalt fibers reduces permeability and water absorption and increases electrical resistivity, indicating lower porosity and stronger bonding between the fibers and the concrete matrix. Moreover, the accelerated corrosion tests confirm that the corrosion rate of steel reinforcement is significantly reduced and the initiation of corrosion-induced cracking is delayed. Overall, the findings of this study highlight that the incorporation of twisted basalt fibers not only improves the mechanical and durability properties of concrete but also plays an effective role in mitigating reinforcement corrosion. Consequently, the use of twisted basalt fibers can be regarded as a novel and efficient approach in the design and construction of reinforced concrete structures in corrosive environments, leading to extended service life, reduced maintenance costs, and enhanced structural sustainability.