The aim of the present work entitled electronic structure of PVA-PEG-Y2O3(54 atom) is to present a theoretical study based on the hybrid function of three parameters Lee-Yang-Parr B3LYP of the density functional theory "DFT" quantum mechanical approach together withLanL2DZbasis sets for optoelectronics applications. The geometric properties included improving geometric optimization (bonds and angles), as electronics properties include ionization potential, electron affinity, chemical hardness, chemical softness, electronegativity, total energy, cohesive energy, energy gap, electrophilicity, and density states, in addition to the spectral properties that involved IR, Raman, and UV-Visible. The results showed that theLanL2DZbasis sets are efficient strongly suggested for heavy metals and give good relax for the structure. The results state that the yttrium oxide has low LUMO-HOMO energy gap, and they have more biological activity ratios. The obtained results indicated that the PVA-PEG-Y(2)O(3)can be used in different fields for electronics and photonics applications such as sensors, transistors, diodes, solar cell, electronic gates, and lasers.