Here, we employed density functional theory-based first-principles computations to examine the structural, electrical, optical, and mechanical properties of NaXO3 (X = Co, Be, Ba) materials. The ideal lattice constants for each of the three materials were fitted using the Birch-Murnaghan method. These compounds have cubic structures with Pm3m-221 space group. According to investigations of the energy band distributions, all of these compounds have indirect band gaps. Calculations also show that NaCoO3 and NaBaO3 compounds have wide bandgap semiconductor properties, while NaBeO3 shows an insulator performance. The degree of electron localization in particular bands is confirmed by TDOS and PDOS. These compounds absorb light more strongly in the ultraviolet region. We discovered that all of these compounds have a mixture of ionic and covalent bonding behavior. We also discovered that the mechanical stability of each of the compounds is simplified by their cubic shapes. These findings not only advance our knowledge of NaxO3 compounds but also create new opportunities for the materials' possible use in a variety of technological contexts. Additionally, these results offer a theoretical foundation for additional experimental research on these materials.