SUMMARY The antineoplastic drug treatment focuses on the inhibition of cell proliferation, those cells which have high mitotic index. However, these drugs are not able to differentiate between healthy cells and the sick. This feature is responsible for a large number of adverse effects, including the alopecia, disorders of the gastrointestinal system, bone marrow depression, changes in behavior and one carcinogenic potential, among others. There are many research groups working in the search for new molecules with potential antineoplastic activity. The composite leaders include tetrahydrocannabinol and endocannabinoids, as anandamide. Recent studies suggest that these compounds offer a high selectivity on diseased cells; this can be considered as a possibility for low risk of toxicity. Finally, all antineoplastic treatments such as of any pathology, should take into account biological rhythms in order to obtain the best therapeutic effects and one less adverse reaction profile. The objective of this work is to understand the mechanisms of action of cannabinoids, the endocannabinoids in cancer and the benefits of future antineoplastic therapy based on the action of these compounds on the growth of cancer cells.