This study provides a comprehensive analysis of the cubic double‐perovskite compound Pb2ScTaO6, exploring its structural stability, electronic, optical, and mechanical properties. The material's response to hydrostatic pressure, using density functional theory with the FP‐LAPW approach, is investigated. The analysis, validated by experimental and theoretical data, reveals Pb2ScTaO6's semiconductor nature with a bandgap of 3.129 eV, which decreases under hydrostatic pressure. Furthermore, the assessment of the material's elastic constants confirms its mechanical stability and the optical properties across ultraviolet and infrared spectra suggest potential applications in optoelectronic devices.