17O chemical shifts of some aromatic carbonyl compounds were measured. The 17O chemical shifts of benzoyl halides correlate with electronegativities of the halides. On the contrary, the 13C chemical shifts of carbonyl carbons do not correlate with the electronegativities of the halides. There is a linear correlation between the 17O chemical shifts and 17O nuclear quadrupole coupling constants. Analysis of 17O chemical shifts according to the Karplus-Pople formula in conjunction with NQR data establishes that the dominant factor influencing the variation of 17O chemical shift is the charge density bond order matrix. The analysis also furnishes information concerning the magnitude of the principal values of the shielding tensor.