Abstract: This study addresses the corrosion and scaling issues of metallic materials in high-salinity environments. Three commonly used scale inhibitors and corrosion inhibitors—polyaspartic acid (PASP), polyepoxysuccinic acid (PESA), and hydroxyethylidene diphosphonic acid (HEDP)—were selected for multi-component formulations. High-throughput screening methods were employed to efficiently identify the optimal component ratios with the best synergistic effects for both scale and corrosion inhibition. The optimal ratios of ternary components of PASP: PESA: HEDP were found to be 1:1:2 and 2:1:1. The corrosion inhibition performance of the selected multi-component inhibitors was then systematically assessed using electrochemical impedance spectroscopy (EIS), and the results showed that the inhibition efficiency at the optimal concentration reached 89.1%. Additionally, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) were used to characterize the corrosion and scaling surfaces of the treated Q235 steel, as well as the crystal structure of the generated CaCO3 precipitates. Further investigation of the mechanisms underlying both scale and corrosion inhibition enabled the development of a rapid and precise approach for assessing the performance of formulated inhibitor systems.