The europium silsesquioxane complexes are synthesized with Eu(NO3)3∙6H2O to corner cap with incomplete condensation of hepta(3,3,3-trifluoropropyl)-tricycloheptasiloxane trisodium silanolate (7F-T7-(ONa)3 along with the 1,3,5,7,9,11,14-hepta isobutyltricyclo [7,3,3,15,14] heptasiloxane-3,7,11-trisilanol (trisilanolisobutyl-POSS). These europium silsesquioxane complexes are highly soluble in organic solvents and show a red emission. Photoluminescence of Eu3+ -CF-POSS is higher compared with Eu3+ -CH-POSS. This fluorescence enhancement is due to the significant effect of the large POSS units. The europium silsesquioxane complexes were characterized by Fourier transform infrared spectrophotometer (FT–IR), field emission scanning electron microscopy (FE– SEM), energy dispersive X-ray analysis (EDX) and thermogravimetric analysis (TGA). The excitation and emission pattern of polyhedral europium silsesquioxanes was studied using photoluminescence spectrophotometer. The results show an excellent emission property at the wavelength between 612 and 620 nm which correspond to the 5D0– 7F2 transition of europium in polyhedral silsesquioxanes. KEYWORDS: Hepta(3,3,3-trifluoropropyl)-tricycloheptasiloxane trisodium silanolate (7F-T7- (ONa)3; trisilanolisobutyl-POSS; Photoluminescence; Eu3+ .