Eight novel N-benzoyl dehydroabietylamine derivatives with potential sterilization and anticancer biological activities were analyzed through electrospray ionization tandem mass spectrometry (ESI-IT-MS). The results indicated that three types of derivatives exhibited their own typical ionization and fragmentation process

due to their different 7-and 12-substituents on the dehydroabietylamine ring and different substituents on the benzoyl ring. In (±)-ESI-MS

the dimer ions of 7-oxime derivatives (A) and 12-nitro derivatives (C) could be more readily formed than that of 7-hydroxy derivatives (B). ［M-H

2

O+H］

+

 of A was observed in the positiveion mode. C were prone to be ionized in the negativeion mode. Two typical fragmentation peaks of ［M-35+H］+ and ［M-H

2

O+H］

+

were observed in (+) -ESI-MS/MS spectra of 7-oxime dehydroabietylamine derivatives . The ion of ［M-H

2

O+H］

+

 formed from 18-acyl of (A) could induce some even fragmentation ion peaks by loss of substituted benzonitrile. The ion of ［M-H

2

O+H］

+

 formed from 7-oxime of (A) can induce some odd fragmentation ion peaks by loss of substituted benzaldehyde. (B) showed more stability than (C) in (-)-ESI-MS/MS process. Fewer fragmentation ions of (B) were obtained even though (B) derivatives were collided with higher energy. Ion fragmentation of (B) and (C) derivatives were induced by loss of neutral molecules of N-substituted benzoyl methylene amine

substituted benzaldehyde or substituted benzene. Due to the strong electronwithdrawing ability of 12and 4-nitro of (C) derivatives

the neutral molecules lost from (C) derivatives can be ionized by capturing one electron.