The　ground-state　electronic/geometrical　structures　of　the　three　C27B　fullerene　isomers　and　the　corresponding　parental　carbon　cage　T-d-C-#2(28),　as　well　as　the　respective　embedded　derivatives　U@C27B　have　been　calculated　at　the　density　functional　theory　level.　The　three　isomers　of　C27B　are　identified　by　theoretical　simulations　of　X-ray　photoelectron　spectroscopy　(XPS),　near-edge　X-ray　absorption　fine　structure　spectroscopy　(NEXAFS).　After　boron　atom　doping,　effective　changes　in　electronic　structure　and　simulated　X-ray　spectra　are　observed.　Analysis　of　the　interaction　between　U　and　fullerenes　C27B　indicates　that　this　is　a　co-stabilizing　effect　resulting　from　the　coexistence　of　ionic　and　covalent　bonds.　This　study　can　contribute　valuable　information　for　further　experimental　and　theoretical　research　on　the　freshly　synthesized　doped　fullerenes　and　their　derivatives　through　the　combination　of　XPS　and　NEXAFS.