Introduction: Soy, Glycine max, Fam. Fabaceae is a species of vegetables originary from East Asia. The vegetal product used both in the pharmaceutical and nutritional area are the beans, Sojae semen. Vegetable soybean is rich in phytochemicals beneficial to the human being and is therefore considered a nutraceutical or a functional food crop. The aim of this study is to test the antiproliferative effect of soy total extract, employing different concentrations, on B164A5 murinic melanoma cell line, using the MTT proliferation assay. Material and method: Soybean seeds were grounded and a solvent formed of DMSO-ethanol-water in 5-70-25 v/v/v ratio was prepared. The extraction was made at room temperature using an ultrasonic bath (Falc LCD Series) for 30 minutes, 59 kHz. The solvent was evapo- rated with a rotary evaporator at 50oC. B164A5 cells were incubated 24 h with 100 μM, 50 μM, 30 μM, 15 μM, 1 μM, 0 μM soy total extract. Results: MTT analysis showed an inhibition of all chosen concentrations of soy total extract. The inhibition was directly proportional with the concentration of soy total extract. Additionally, a change in the number and morphology of B164A5 cells was noticed starting from the concentration of 15 μM. Conclusion: Our results suggest that soy total extract presents an antiproliferative effect in vitro on B164A5 murinic melanoma cell line.