Objectives: The aim was to determine the effect of hybrid quinoline molecules on growth of normal cell line and tumour cell lines. Study design: Experimental study Materials and methods: Effect of quinoline hybrids was determined on colon adenocarcinoma (CaCo-2), breast adenocarcinoma (MD-AMB-231), acute lymphoblastic leukemia (CCRF-CEM) cells, and on Madin-Darby Canine Kidney fibroblast-like cells (MDCK1) as normal cells. Cytotoxicity was tested using an MTT assay after 72 hours of incubation with new quinoline hybrids at concentration span from 1 x 10-4 M to 1 x 10-6 M. Flow cytometry was used to determine changes in cell cycle distribution in CaCo-2, MDAMB231 and CCEF-CEM cells treated with 5 x 10-6 M of quinoline hybrids for 24h. Results: Hybrids exhibit citotoxic effect on all cell lines at concentrations of 1 x 10-4 M and 1 x 10-5 M. MDCK1 cells only showed a statistical significance at a concentration of 1 x 10-4 M. QH3 caused significant changes in cell cycle with CaCo-2 in G1 phase, MDA-MB-231 cells in S phase, and CCRF-CEM in both G1 and S phase. Conclusion: Tested quinoline hybrids showed dose dependent cytotoxic effect on treated cells, which differed between cell lines. MDCK1 cells were more resistant to quinoline hibrids than tumour cells. QH3 hybrid exhibited the highest cytotoxicity. The cytotoxic effect on normal cells was lower than on the tumour cells. All hybrids exhibited cytotoxicity, but only QH3 caused significant changes in the cell cycle. Quinoline hybrids show promising results in cancer treatment but further biological evaluation is required.