Abstract: To address the technical challenges in achieving high-quality rolling strengthening for 45CrNiMoVA steel components with circular arc surfaces, an experimental study on the rolling strengthening integrity of these surfaces was conducted. Through orthogonal rolling tests and grey relational analysis, the influence laws of rolling parameters on surface integrity were investigated and the optimal parameter combination was obtained. SEM and EBSD tests were utilized to reveal the formation of surface integrity and the microstructure strengthening mechanism. After optimization, the surface residual compressive stress reaches −660.54 MPa, and the affected layer depth reaches 1.2 mm. The maximum axial residual compressive stress is −1 186.78 MPa, the surface hardness reaches 613.50 HV, and the surface roughness decreases to 0.61 μm. After optimized strengthening, the surface grain size decreases to 0.784 μm, which is 4.27% lower than that of the grinding process. The geometrically necessary dislocation density increases to 1.138 × 10¹⁴ m⁻², showing a 0.53% increase over grinding. The orientation density decreases to 1.6, representing a 40.74% reduction compared to grinding. This optimized process significantly enhances the surface integrity of 45CrNiMoVA steel arc workpieces. This study provides a crucial parametric basis for the application of deep rolling in the circular arc regions of 45CrNiMoVA torsion bar springs.