The Umbelliferone (UMB)molecule was optimized by density functional theory with B3LYP/6-311G (d,p) and HF /6-311G (d, p) basis set. The time-dependent DFT method was engaged to calculate the Frontier Molecular orbitals (FMOs) of the UMB molecule. The reactivity and selectivity of UMB are analyzed using parameters like MEP, global reactivity descriptors, Fukui function. Mulliken atomic charges are calculated and interpreted. The TDOS, PDOS and OPDOS of the molecule have been plotted and interpreted. Thermodynamic properties of the title molecule calculated.The molecular docking analysis reveals that inhibitory nature of the UMB molecule is a proved inhibitor of thePI3K inhibitor activity.