**5. Conclusions**

Alkaloids are the main constituents of *Zanthoxylum* species, present in the fruits, leaves, bark and root of plants. There are different types of skeletons of these alkaloids, including benzophenanthridines, aporphines, benzylisoquinolines, furoquinolines, quinolines, quinolones, quinazolines, indolopyridoquinazolines, acridones, canthinones, amines and tryptamines; in which benzophenanthridines are the main ingredient. Alkaloids from *Zanthoxylum* species have been displayed a variety of valuable biological activities, such as antibacterial, antifungal, antiviral, anti-inflammatory, antioxidant, cardiovascular protect and especially anti-cancer effects. Some alkaloids of which shown their potential to become natural healing agents, this has increasingly attracted scientists' interest in the genus *Zanthoxylum*. The data collected in this chapter has clearly shown that *Zanthoxylum* alkaloids with abundance of chemical structures and a wide range of cytotoxic activities on many the cancer cell lines. These could be good sources of potential cancer chemopreventive agents. Further studies should be carried out to know more clearly the anticancer mechanisms of these alkaloids.
