The hydrostatic-pressure-dependent mechanical stability and optoelectronic behavior of Zn4B6O13 (ZBO) are calculated using the exchange-correlation functional Perdew-Burke-zerhof generalized gradient approximation and the hybrid functional PBE0 based on density functional theory.The calculated and experimental unit cell volumes and Vickers hardness of ZBO at zero pressure agree well.ZBO is mechanically stable under the critical pressure of 52.98 GPa according to the generalized stability criteria.Furthermore,Young’s modulus and Vickers hardness decrease with increasing hydrostatic pressure.The strength and type of ZBO bonds are investigated by population and electron density difference.The electronic structure at zero pressure reveals that ZBO is an indirect band gap semiconductor,and the calculated 5.62-eV bandgap coincides well with the 5.73-eV experimental value,highlighting the success of the hybrid functional PBE0 calculations of electronic properties.The band gap almost increases as a second-order polynomial of pressure,and the indirect nature does not change with the applied extal pressure.The optical reflectivity and absorption coefficient show that ZBO is an excellent ultraviolet photodetector.Our calculation results suggest that the elastic and optical properties of ZBO are highly stable over a wide pressure range.