Chelidonine is the major alkaloid component of Chelidonium majus. Chelidonine is an isolate of Papaveraceae with acetylcholinesterase and butyrylcholinesterase (a nonspecific cholinesterase) inhibitory activity. It showed strong cytotoxicity in cancer cells. While several modes of death have been identified, most of anti-cancer attempts have focused on stimulation of cells to undergo apoptosis. Chelidonine seems to trigger multiple mechanisms in MCF-7 breast cancer cells. It induces both apoptosis and autophagy modes of cell death in a dose dependent manner. Alteration of expression levels of bax/bcl2, and dapk1a by increasing concentration of chelidonine approves switching the death mode from apoptosis induced by very low to autophagy by high concentrations of this compound. On the other hand, submicromolar concentrations of chelidonine strongly suppressed telomerase at both enzyme activity and hTERT transcriptional level. Long exposure of the cells to 50 nanomolar concentration of chelidonine considerably accelerated senescence. Altogether, chelidonine may provide a promising chemistry from nature to treat cancer. Chelidonine exhibits a broad spectrum of pharmacological properties, such as anti-inflammatory and antiviral activities Its biological activities and clinical applications have been extensively investigated. Especially the usage of chelidonine as an anticancer drug is very important lately. It also has profound inhibitory effects on airway inflammation, which means chelidonine can improve allergic asthma in mice and may also work for human medicine.