Cannabidiol was ionized under Electrospray Ionization Mass Spectrometry (ESI-MS) and Atmospheric Pressure Chemical Ionization Mass Spectrometry (APCI-MS) to obtain precursor ions. Afterward, chosen precursor ions were fragmented into their product ions with their mass-to-charge ratios (m/z) under Tandem Mass Spectrometry (MS/MS). From m/z of the product ions, their structural features were suggested. Afterward, derivatives of cannabidiol were ionized under ESI-MS and fragmented into their product ions under MS/MS. Structural informations were obtained from m/z as in the cannabidiol studies.