The exploration of the hydrostatic pressure effect on the characteristics of materials is essential for various applications. Our study uses Density Functional Theory (DFT) to investigate the pressure-induced influence on the structural, electronic, optical, and mechanical properties of BaCeO3. According to formation enthalpy and Born stability criteria, BaCeO3 is mechanically and thermodynamically stable from 0 GPa to 80 GPa. The tunable band gap of BaCeO3 within the visible spectrum under applied pressure makes it a potential candidate for absorber layer fabrication of solar cells. The electronic state, mainly attributed to O-2p in the valence band (VB) and Ce-4f in the conduction band (CB), is observed through Partial Density of States (PDOS), although its intensity varies with pressure. The refractive index shows that pressurized BaCeO3 is appropriate for photonics. Its significant absorption at high energy under pressure makes it an excellent candidate for Ultraviolet (UV) detectors, and it also has low light reflection, with static values routinely less than 0.2. Additionally, as pressure increases, elastic constants, elastic moduli, ductility, machinability index, and anisotropy all increase, except for hardness, which decreases. BaCeO3 is approaching to minimal bond stretching with pressure according to Kleinman parameter. These pressure-induced changes in mechanical properties have potential applications in flexible electronics, structural uses, and more.