Cervical cancer is the second most common cancer of women in the world. The treatment for this type of cancer includes chemotherapy, radiotherapy, and in more severe cases surgery is necessary, thus being highly invasive for these women, and so we see the search for new treatments that can help in the treatment. Melatonin is a hormone known to be produced by the pineal gland and to participate in the regulation of the circadian rhythm, and studies show that it has antitumor activity by several mechanisms, including its antiproliferative and pro-apoptotic effects, besides its potent pro-oxidant action on tumor cells, As it is known about the excellent and achievements of this molecule, this work aims to observe how it acts and how these changes may participate in the tumorigenic process in cervical cancer, HeLa and SiHa lines, and in normal skin cell (HaCaT) through morphological aspects, cytotoxicity, nuclear damage, cell cycle and migration, genotoxicity, apoptosis, cell cycle and gene expression, observing how this action occurs and how these changes may participate in the tumorigenic process. After treatment with melatonin the results found in these strains were positive, we observed that melatonin did not alter cell morphology, but reduced cell proliferation and migration, was not cytotoxic, but was genotoxic, reduced tumor colony formation, induced the process of early and late apoptosis and necrosis, and stimulated cells to park in the G1/G0 and G2/M phases of the cell cycle. In addition, we observed that melatonin also modulated the PI3K/AKT gene pathway by activating MTNR1A and MTNR1B receptors and decreasing AKT. Thus, melatonin seems to present an antitumorigenic action, by mechanisms related to antiproliferative, antimigratory and apoptotic pathways.