The present work investigates the influence of Selective Laser Melting (SLM) process parameters on the hardness and surface roughness of S2507 stainless steel using experimental investigation, statistical modelling, and response optimization. A Design of Experiments (DOE) approach was employed by varying laser power (200–250 W), scan speed (700–1000 mm/s), and hatch distance (30–50 µm). Regression modelling, Analysis of Variance (ANOVA), correlation analysis, and response optimization were used to evaluate the effects of these parameters. Scan speed was identified as the most influential parameter for both responses, exhibiting a strong inverse relationship with hardness and surface roughness, while hatch distance showed a positive secondary influence. Laser power had a comparatively smaller practical effect within the investigated range. The hardness regression model exhibited strong predictive performance, with R² and predicted R² values of 97.88% and 91.17%, respectively. Response optimization predicted a maximum hardness of 482.20 VHN at 250 W laser power, 700 mm/s scan speed, and 50 µm hatch distance. The surface roughness model also demonstrated good prediction capability, with R² and predicted R² values of 93.78% and 78.49%, respectively. The experimentally measured minimum surface roughness was 7.06 µm at 250 W laser power, 1000 mm/s scan speed, and 30 µm hatch distance, while the regression-based response optimization predicted a minimum value of 6.85 µm at 200 W, 1000 mm/s, and 30 µm. The results demonstrate the importance of balancing hardness and surface quality when selecting SLM processing conditions for S2507 stainless steel components.