Metallic nanoparticles (NPs) possess unique properties which makes them attractive candidates for various applications especially in field of experimental medicine and drug delivery. Many approaches were developed to synthesize divers and customized metallic NPs that can be useful in many areas such as, experimental medicine, drug design, drug delivery, electrical and electronic engineering, electrochemical sensors, and biochemical sensors. Among different metallic nanoparticles, manganese (Mn) NPs are the most prominent materials, in the present study, we have synthetized unique Mn0.5Zn0.5EuxDyxFe1.8-2xO4 NPs by using ultrasonication method (x <= 0.1). The structure, and surface morphology of Mn0.5Zn0.5EuxDyxFe1.8-2xO4 NPs was characterized by XRD, SEM, TEM and EDX methods. We have examined the biological effects of Mn0.5Zn0.5EuxDyxFe1.8-2xO4 NPs on both normal (HEK-293) and cancerous (HCT-116) cells. We have found that the treatment of Mn0.5Zn0.5EuxDyxFe1.8-2xO4 NPs post 48 h, showed significant decline in cancer cells population as revealed by MIT assay. The IC 50 value of Mn(0.5)Zn(0.5)Eu(x)Dy(x)Fe(1.8-2x)O(4 )NPs was ranged between (2.35 mu g/mL to 2.33 mu g/mL). To check the specificity of the actions, we found that the treatment of Mn(0.5)Zn(0.5)Eu(x)Dy(x)Fe(1.8-2x)O(4 )NPs did not produce any effects on the normal cells, which suggest that Mn0.5Zn0.5EuxDyxFe1.8-2xO4 NPs selectively targeted the cancerous cells. The anti-bacterial properties of Mn0.5Zn0.5EuxDyxFe1.8-2xO4 NPs were also evaluated by MIC and MBC assays. We suggest that Mn0.5Zn0.5EuxDyxFe1.8-2xO4 NPs produced by sonochemical method possess potential anti-cancer and anti-bacterial capabilities.