We have used chemical ionization (CI) mass spectrometry to analyze several carbohydrates such as D-glucose and D-sucrose, their trimethylsilyl (TMSi) derivatives, and several carbohydrate esters. Results were obtained from analysis by gas chromatography/mass spectrometry (GC/MS) as well as analysis by direct chemical ionization (DCI). In both cases the preferred reagent gas is ammonia, since it gives structural and molecular weight information. Other reagent gases used include methane, isobutane, and a mixture of nitric oxide in nitrogen. A tobacco isolate consisting of carbohydrate esters was analyzed using the DCI technique, giving mass spectra which are indicative of sucrose tetraesters substituted on only one of the saccharide units. Substituents include valerate, methylvalerate, and acetate esters.