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In addition to the three influencing factors of Cl- content, temperature, and pH, factors such as microbial corrosion and fluid flow rate also affect the pitting behavior of stainless steel used in oil and gas field environments, alongside the equipment and pipelines there. Microorganisms in oilfield produced water are an important factor causing material corrosion. The metabolic products of sulfate-reducing bacteria can promote the destruction and dissolution of the passive film on the surface of stainless steel. When the mass concentration of Cl- is 30 g/L, the metabolism of sulfate-reducing bacteria is at its peak. Generally, the flow rate of the medium promotes the diffusion of reactants and accelerates the detachment of surface corrosion products, making it difficult for a dense protective film to form on the stainless steel surface. Furthermore, the fluid exerts a scouring effect on the stainless steel surface, thereby promoting the occurrence of local corrosion such as pitting. At temperatures of 70–100°C and flow rates below 78.2 m/s, a thicker film of corrosion products can form on the surface of ordinary 13Cr stainless steel, whereas the film formed on the surface of super 13Cr stainless steel is relatively thinner. When the flow velocity is less than 3 m/s, the corrosion rate of 13Cr steel increases as the flow velocity increases, and is proportional to the 0.5 power of the flow velocity; however, when the flow velocity exceeds 3 m/s, the corrosion rate remains essentially unchanged regardless of changes in flow velocity.