A new series of half-sandwich ruthenium(II) compounds [(η-arene)Ru(L)Cl][CFSO] bearing 1,2,3-triazole ligands (arene = -cymene, L = (); arene = -cymene, L = (); arene = benzene, L = (); arene = benzene, (); = 2-[1-(-tolyl)-1-1,2,3-triazol-4-yl]pyridine and = 1,1'-di--tolyl-1,1'-4,4'-bi(1,2,3-triazole) have been synthesized and fully characterized by H and C NMR and IR spectroscopy, mass spectrometry, and elemental analysis. The molecular structures of , , and have been determined by single-crystal X-ray diffraction. The cytotoxic activity of - was evaluated using the MTS assay against human tumor cells, namely ovarian carcinoma (A2780), colorectal carcinoma (HCT116), and colorectal carcinoma resistant to doxorubicin (HCT116dox), and against normal primary fibroblasts. Whereas compounds and showed no cytotoxic activity toward tumor cell lines, compounds and were active in A2780, while showing no antiproliferative effect in human normal dermal fibroblasts at the IC concentrations of the A2780 cell line. Exposure of ovarian carcinoma cells to IC concentrations of compound or led to an accumulation of reactive oxygen species and an increase of apoptotic and autophagic cells. While compound displayed low levels of angiogenesis induction, compound showed an ability to induce cell cycle delay and to interfere with cell migration. When the toxicity studies using zebrafish and chicken embryos are considered, compounds and , which were not lethal, are promising candidates as anticancer agents against ovarian cancer due to their good cytotoxic activity in tumor cells and their low toxicity both and .