In this manuscript, a borate ester solution, as a precursor, is prepared by combining polyvinyl alcohol (PVA) and boric acid (BA). The precursor is then electrospun to form nanofibers. However, the addition of BA has a negative effect on the spinning behavior by changing the conductivity. The solution's quality is enhanced through use of additives such as glycerol, sodium chloride, and acetic acid. The effect of additives on the viscosity and conductivity of solutions, and their spinning behavior, is investigated. By adjusting electrospinning process variables and solution properties, nanofibers are produced. Fourier transform infrared (FT‐IR) analysis is performed to identify the formation of borate ester as a result of the reaction between PVA and BA. Thermal analysis is used to characterize the thermal stability of the fibers. Scanning electron microscopy (SEM) is used to examine the fiber morphology and diameter distribution. The findings are used to determine the best viscosity–conductivity windows for the production of electrospun borate ester nanofibers. Finally, the ability of optimized nanofibers to capture neutrons is evaluated using an Am‐Be neutron source and a BF3 detector set up. The results of the measurements indicate that the incorporation of BA into PVA nanofibers can enhance their neutron shielding capabilities up to 7.3%.