The present study investigates the impact of sulfate attack on the durability of reinforced ‎cement composites containing steel and polypropylene fibers, as well as silica nanoparticles. ‎To this end, varying weight percentages (1%, 2%, and 3%) of silica nanoparticles replaced ‎cement, and 1% by weight of steel fibers and 0.2% by weight of polypropylene fibers were ‎separately and concurrently added as micro-scale additives to the cement composite exposed ‎to sulfate attack. Consequently, the formulated cement composites underwent a 6-month ‎exposure to a 5% sodium sulfate solution, and the effects of the sulfate environment on ‎changes in compressive strength, weight, and longitudinal expansion of the specimens were ‎studied. The results indicate that the simultaneous presence of silica nanoparticles, steel ‎fibers, and polypropylene leads to increased durability against sulfate attack. Specifically, ‎the composite with 2% silica nanoparticles, 1% steel fibers, and 0.2% polypropylene fibers ‎exhibited the least reduction in compressive strength, mass loss, and longitudinal expansion ‎after 6 months of immersion in the sulfate solution compared to other formulations. ‎According to the findings, the concurrent presence of silica nanoparticles and steel and ‎polypropylene fibers in the cement matrix significantly enhances the durability of cement-‎based composites against sulfate attack.‎