In this study, tin oxide (SnO2) thin films were deposited on glass substrates by RF magnetron sputtering, with process parameters optimized by adjusting the oxygen flow rate. Subsequently, thermal treatment was performed at various temperatures in a vacuum environment. The thickness, electrical conductivity, optical transmittance, and figure of merit (FOM) of the films were analyzed. The results indicate that the films deposited with an oxygen flow rate of 5 sccm, a sputtering power of 80 W, and a deposition time of 30 min, followed by annealing at 200 ℃, exhibited the highest performance. Specifically, the films achieved a minimum resistivity of 3.19 × 10−2 Ω·cm and an optimal FOM of 7.43 × 10−5 Ω−1. These findings demonstrate excellent optoelectronic properties, suggesting high potential for applications in optoelectronic sensor materials.